METHOD AND SYSTEM FOR CONTROLLING EFFICIENCY OF HEATING SYSTEM

BACKGROUND OF THE INVENTION

The invention relates generally to a heating system. More particularly, the invention relates to a system and method of controlling efficiency of a combination water heating and space heating system to provide hot water supply and space heating. The heating system demonstrates fluid isolated systems in a heating device. The two or more fluid isolated systems in the heating device are capable of modulating the transfer of energy between systems using a heat exchanger while retaining individual system fluid isolation.

Combination water heating and hydronic heating systems are used for both domestic and space heating purposes. In such combination systems, heated fluid is circulated between a storage tank and a hydronic heat exchanger based upon demand to provide heated air and domestic hot water.

Hydronic heating systems transfer heat generated from combustion to fluid in the hydronic heating system. The heated fluid then conducts through fins and pipe walls to a particular space. Oftentimes, the equipment to perform hydronic heating requires installation of additional and separate parts over and above those used for domestic water heating.

Solar energy, for example energy collected in roof mounted solar collector, may be used a heat source for various types of household or industrial heating, for example a radiant heating system and domestic hot water. Solar energy is a renewable energy source, and thus utilization of solar energy in heating systems is highly desirable from an environmental perspective. As concern regarding global warming and other undesirable environmental affects of fossil fuels increase, it has become increasingly important to harness solar energy in today's heating systems.

In view of the foregoing, there is a desire to integrate a high-efficiency heating unit providing both domestic hot water and space heating within one compact, efficient heating device. Further, there is a desire to provide a method for operating a combination water heating and space heating system more efficiently. In addition, there is a desire to use solar energy to increase the overall efficiency in a compact heating device.

BRIEF SUMMARY OF THE INVENTION

The invention preserves the well known advantages of prior methods and systems provided for controlling efficiency of a heating system. In addition, the invention provides new advantages not found in currently available methods and systems, and overcomes many disadvantages of the currently available methods and systems provided for controlling efficiency of a heating system.

A method and system is provided for controlling efficiency of a heating system. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system. The heating system demonstrates fluid isolated systems in a heating device. The two or more fluid isolated systems in the heating device are capable of modulating the transfer of energy between systems using a heat exchanger while retaining individual system fluid isolation.

The heating system includes a heat exchanger for transferring heat connected between a primary fluid system having a hot water supply and a secondary fluid system for space heating. Generally, the primary fluid system includes a storage container, temperature sensors, a heating assembly, a heating element, and a storage pump. The storage container for holding storage fluid having an inlet and outlet for storage fluid. An upper temperature sensor and a lower temperature sensor are attached to the storage container for measuring the temperature. A heating element is substantially positioned within the storage container for increasing a temperature of the storage fluid. A storage pump for delivering storage fluid from the storage container to the heat exchanger. A temperature sensor for measuring the temperature of the storage fluid returning from the heat exchanger to the storage container.

Generally, the secondary fluid system includes a heating supply structure for containing a heating supply fluid, a temperature sensor for measuring a temperature of the heating supply fluid from the heat exchanger, and a heating supply pump in connection with the heating supply structure for circulating the heating supply fluid.

In addition, the heating system for controlling efficiency may optionally include a solar energy system. Generally, the solar energy system includes a solar energy collector, a solar energy sensor, a solar pump, a solar input member, and a vertex sensor. The solar energy collect or solar panel absorbs solar energy and a temperature of the solar collector is measured by the solar energy sensor. A solar pump is provided for circulating a solar energy fluid from the solar connector to a solar input member. The solar input member may be positioned within a storage tank to transfer heat from the solar energy fluid of the solar input member to the storage fluid. A vertex sensor is measures the temperature of the solar energy fluid after it returns from the solar input member.

In operation, the heating system demonstrates fluid isolated systems in a single device. During operation, fluid isolation occurs between the primary fluid system having an open loop with a storage container, the secondary fluid system having a closed loop with a heating supply structure, and an optional solar energy system having solar energy fluid. The two or more fluid isolated systems are capable of modulating the transfer of energy between systems while retaining individual system fluid isolation.

Another system for controlling the efficiency of a heating system includes a combination hot water supply and space heating system. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system. In particular, a heat exchanger for transferring heat is connected between a primary fluid system providing a heating supply fluid for space heating to a secondary fluid system having a storage fluid for domestic usage.

Generally, the primary fluid system includes a container for storing heating supply fluid, a heating assembly, a heating element, a heating supply structure, a fluid supply pump, a fluid circulating pump, temperature sensors, and a heat exchange pump. The container includes an upper temperature sensor and a lower temperature sensor with a heating element substantially positioned within the storage for increasing a temperature of the heating supply fluid. The heating supply structure is connected to the container for storing fluid. The fluid supply pump is connected to the heating supply structure and the container for delivering heating supply fluid to the heating supply structure. The fluid circulating pump is connected to the heating supply structure used for circulating heating supply fluid through the heating supply structure and back to the container. A first temperature sensor is connected to the heating supply structure for measuring the temperature of the heating supply fluid within the heating supply structure. A heat exchange pump is provided for delivering heating supply fluid from the container to the heat exchanger. A second temperature sensor is connected between the heat exchanger and the container to measure the temperature of the heating supply fluid.

The secondary fluid system includes an inlet for storage fluid connected to the heat exchanger, a temperature sensor connected between the inlet and the heat exchanger to measure the temperature of the storage fluid entering through the inlet, a flow sensor for measuring the flow of storage fluid exiting the heat exchanger, a temperature sensor for measuring the temperature of the storage fluid exiting the heat exchanger, and an outlet for storage fluid connected to the heat exchanger.

The method for controlling efficiency of a heating system includes the following steps as outlined herein. First, a heating system is provided which is capable of adjusting a temperature of storage fluid and radiant supply fluid. The temperature of the storage fluid is measured and has an initial temperature setting. The internal temperature of the storage fluid is adjusted if an external temperature is above warm weather shutdown temperature. If external temperature is below warm weather shutdown temperature, the internal temperature of the storage fluid is adjusted.

The method for controlling the efficiency of a heating system further includes controlling a temperature of a radiant supply fluid of the heating system. First, the temperature of the radiant supply fluid and storage fluid is measured. The temperature of the radiant supply fluid is compared with the temperature of the storage fluid. The temperature of the radiant supply fluid is increased to a radiant supply temperature set point by increasing flow rate of storage fluid having a higher temperature to heat exchanger. In addition, the temperature of the storage fluid is increased if storage fluid temperature is below the radiant supply temperature.

The method for controlling efficiency of the heating system may also include solar energy fluid. First, the temperature of the solar energy fluid and the storage fluid is measured. Next, the temperature of the solar energy fluid and the storage fluid are compared. The temperature of the storage fluid is increased to a storage fluid set point by increasing the flow rate of solar fluid having a higher temperature.

It is therefore an object of the present invention to provide a method and system for controlling the efficiency of the heating system.

A further object of the present invention is to provide water heating and space heating capabilities in a compact, efficient heating unit.

Another object of the present invention is to provide a compact, efficient heating unit which includes two or more isolated fluid systems that can modulate energy transferred between the systems.

It is a further object of the present invention is to provide a method for adjusting the temperature of the storage fluid based upon external temperature.

Yet another object of the present invention is to provide a method for controlling a temperature of a radiant supply fluid of the heating system.

Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features, which are characteristic of the method and system for controlling efficiency of a heating system, are set forth in the appended claims. However, the method and system for controlling efficiency of the heating system, together with further embodiments and attendant advantages, will be best understood by reference to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of an integrated heating device which provides a hot water supply and space heating combined in an integrated heating unit;

FIG. 2 is a schematic illustration of a heating system providing a hot water supply and space heating;

FIG. 3 is a schematic illustration of an alternative heating system providing a hot water supply and space heating;

FIG. 4 is a schematic illustration of a solar heating system providing a hot water supply and space heating;

FIG. 5 is a schematic illustration of an alternative solar heating system capable of providing a hot water supply;

FIG. 6 a schematic illustration of an another alternative solar heating system capable of providing a hot water supply;

FIG. 7 is a bar graph providing an example of solar energy and fuel usage for the solar heating system;

FIG. 8 is a line chart providing storage fluid set points relative to outside temperature;

FIG. 9 is a line chart providing storage fluid set points relative to radiant supply temperature;

FIG. 10 is line chart providing storage fluid set points relative to inlet temperature of fluid during summer mode;

FIG. 11 is a line chart providing storage fluid set points relative to inlet temperature during winter mode and radiant supply fluid setpoint;

FIG. 12 is a line chart providing storage fluid set points relative to inlet temperature of fluid;

FIG. 13 is a front view of an alternative heating device which is capable of providing a hot water supply and space heating;

FIG. 14 is a front view of a domestic hot water module for connection with the alternative heating device of FIG. 13;

FIG. 15 is a front view of a space heating module for connection with the alternative heating device of FIG. 13;

FIG. 16A is a left side view of the alternative heating device of FIG. 13;

FIG. 16B is a right side view of the alternative heating device of FIG. 13;

FIG. 17 is a front view of the alternative heating device of FIG. 13 with an optional heating module;

FIG. 18 is a front view of the alternative heating device of FIG. 13 with a domestic hot water module of FIG. 14;

FIG. 19 is a front view of the alternative heating device of FIG. 13 with a space heating module of FIG. 15;

FIG. 20 is a front view of an alternative solar heating device which is capable of providing a hot water supply and space heating;

FIG. 21 is a front review of a space heating module for connection with the alternative solar heating device;

FIG. 22 is a front view of the alternative solar heating device of FIG. 20 with a space heating module of FIG. 21;

FIG. 23A is a left side view of the alternative solar heating device of FIG. 20;

FIG. 23B is a front view of the alternative solar heating device of FIG. 20; and

FIG. 23C is a right side view of the alternative solar heating device of FIG. 20.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Generally referring to FIGS. 1-23, the present method and system solves a disadvantage of the prior art by providing a new and unique method and system for controlling efficiency of the heating system. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system which may have one or more configurations.

Referring to FIG. 1, the heating system demonstrates fluid isolated systems in a compact, efficient heating device 10 that saves on piping, wiring, space, and cost. The two or more fluid isolated systems in the heating device are capable of modulating the transfer of energy between systems (space heating and domestic hot water) using a brazed plate heat exchanger while retaining individual system fluid isolation. This heating device is highly efficient combustion system, in one embodiment up to 96% thermal efficiency, by providing the amount of energy needed without sacrificing comfort.

In one embodiment, the heating device illustrated in FIG. 1, is configured with the following components. The heating device includes a storage container made of stainless steel or other materials with a 2″ foam insulation wrapped in a plastic outer dent/rust resistant outer jacket for storage of fluid that provides approximately ½ degree heat loss per hour. The storage container for holding storage fluid having an inlet and outlet for storage fluid with built in hydraulic stabilization. The hot water outlet dip tub draws all of the hot water from the top of the container to improve the amount of hot water delivery from the container. A cold water inlet at the bottom of the storage tank feeds cold water to help remove sediment from the bottom of the container. An upper temperature sensor and a lower temperature sensor are attached to the storage container for measuring the temperature to control burner input. A combustion heat exchanger or heating element generally in a shape of a helical shape made of stainless steel/cupronickel or other materials for heating the storage fluid of the container. A heating assembly comprising a modulating burner assembly with a 3 to 1 turndown for heating the heating element. The heating element is substantially positioned within the storage container for increasing a temperature of the storage fluid. A storage pump, preferably variable speed pump, which allows for modulating flow of heated fluid from a storage container to accurately control fluid or radiant supply temperature. The storage pump delivers storage fluid from the storage container to the brazed plate heat exchanger whereby heat is transferred from the storage fluid to the radiant fluid supply. A temperature sensor is used for measuring the temperature of the storage fluid returning from the brazed plate heat exchanger to the storage container. The heating unit has a domestic hot water inlet and domestic hot water outlets. The heating unit also has system inlet and outlet connections for connection with various applications including hydronic baseboard, radiant, and hydro-air systems. It should be noted that a heat exchanger other than a brazed plate heat exchanger may be used in the present invention.

In operation, the heating device of FIG. 1 draws storage fluid through the inlet into the interior of the storage container. To achieve a set storage fluid temperature, the heating element or burner assembly will fire to deliver heat through the combustion heat exchanger which will increase the temperature of the storage fluid. If a demand for domestic hot water is received by a controller, the controller will activate the pump to deliver domestic hot water through an outlet. If a demand for space heating is received by a controller, the controller will activate a pump to deliver heated storage fluid to the brazed plate heat exchanger to transfer heat to a radiant supply fluid. The radiant supply fluid will then, in turn, circulate through an external radiant heating loop through the system inlets and outlets. Throughout the operation of this heating device, temperature sensors for the storage fluid and radiant supply fluid will monitor and send feedback to the controller to process and calculate the desired temperature set points for the storage fluid and radiant or heating supply fluid. The heating device of FIG. 1 combines the applications of both space heating and domestic hot water in one single appliance in accordance with the methods and systems further described below.

Referring to FIG. 2, a heating system 20 is provided with a storage container or tank as an open loop for direct hot water supply and large mass heating closed loop with modulation of energy transfer using variable inputs of heating assembly and pump to provide high efficiency of energy transfer. It should be appreciated that the heating systems of the present invention may be configured in more than one way and this is merely an example of one particular configuration with isolated fluid systems in a heating system. The heating system includes a heat exchanger for transferring heat and is connected between a primary fluid system having a hot water supply and an additional secondary fluid system for space heating. In one embodiment, the heat exchanger and the primary fluid system are contained within a single, compact, efficient heating device as illustrated in FIG. 1. Generally, the primary fluid system includes a storage container, temperature sensors, a heating element, and a storage pump. The storage container for holding storage fluid having an inlet and outlet for storage fluid with built in hydraulic stabilization. An upper temperature sensor and a lower temperature sensor are attached to the storage container for measuring the temperature. A heating element is substantially positioned within the storage container for increasing a temperature of the storage fluid. A storage pump for delivering storage fluid from the storage container to the heat exchanger. A temperature sensor for measuring the temperature of the storage fluid returning from the heat exchanger to the storage container.

Generally, the additional secondary fluid system may include a heating supply structure for containing a heating supply fluid, a temperature sensor for measuring a temperature of the heating supply fluid from the heat exchanger, and a heating supply pump in connection with the heating supply structure for circulating the heating supply fluid.

During operation, fluid isolation occurs between the primary fluid system having an open loop with a storage container, the secondary fluid system having a closed loop with a heating supply structure, and an optional solar energy system having solar energy fluid. The two or more fluid isolated systems are capable of modulating the transfer of energy between systems while retaining individual system fluid isolation.

In operation, the system of FIG. 2, operates to control the efficiency of the heating system. To achieve a set storage fluid temperature, the burner assembly will fire to deliver heat through the heating element which will increase the temperature of the storage fluid. If a demand for domestic hot water is received by a controller, the controller will activate the pump to deliver domestic hot water through an outlet. If a demand for space heating is received by a controller, the controller will activate a pump to deliver heated storage fluid to the brazed plate heat exchanger to transfer heat to a radiant supply fluid. The radiant supply fluid will then, in turn, circulate through an external radiant heating loop through the system inlets and outlets. Throughout the operation of this heating device, temperature sensors for the storage fluid and radiant supply fluid will monitor and send feedback to the controller to process and calculate the desired temperature set points for the storage fluid and radiant or heating supply fluid which can be modulated by operating pumps to deliver storage fluid to the heat exchanger at a defined flow rate and temperature to increase the temperature of the heating supply fluid.

Referring to FIG. 4, a heating system 40 for controlling efficiency may optionally include a solar energy system having a control over the alternative energy input into the storage container open loop. The heating system of FIG. 2 with the optional solar energy system provides advantages including reduces fuel input by continuously control and monitoring two systems, reduces electrical input by variable speed pumping, high heat load compensation by temporarily boosting tank temperatures, and energy transfer monitoring through control outputs and sensor inputs. Generally, the solar energy system includes a solar energy collector, a solar energy sensor, a solar pump, a solar input member such as a solar heat exchanger, and a vertex sensor. The solar energy collect or solar panel absorbs solar energy and a temperature of the solar collector is measured by the solar energy sensor. A solar pump is provided for circulating a solar energy fluid from the solar connector to a solar input member. The solar input member may be positioned within a storage tank to transfer heat from the solar energy fluid of the solar input member to the storage fluid. A vertex sensor is measures the temperature of the solar energy fluid after it returns from the solar input member.

In operation, the method for controlling efficiency of the heating system may also include a solar energy system having solar energy fluid. First, the temperature of the solar energy fluid and the storage fluid is measured. Next, the temperature of the solar energy fluid and the storage fluid are compared. The temperature of the storage fluid is increased to a storage fluid set point by increasing the flow rate of solar fluid having a higher temperature. The solar energy system controls and records the amount of energy absorbed via solar while continuously controlling for total system efficiency.

Referring to FIGS. 5-6, the operation of the solar energy system 50, 60 is described herein in more detail. Note, the solar energy system herein may include or not include a radiant heating loop. When the panel is a specified temperature above the tank temperature, the system will begin pumping fluid to absorb the solar energy. For pressurized systems the pump will start slow, and slowly increase to maintain a solar gain and avoid short cycling. For a drain back system the pump will start on high speed for a specific length of time to charge the system. After specified length of time the pump will decrease and be controlled for more solar gain. The pump will continue to run with either system under a PID control to maintain the temperature of the panels a specified temperature above the tank temperature. This will continue until one of two things happen. One there is no longer a great enough difference in temperature between tank and panels to obtain solar gain. Or two the tank has reached its maximum set point. The NHX configuration will have a similar operation, with the addition of a solar circulation pump that will run when the storage tank is warmer than the evolution NHX. The system I/O, program parameters, visual display, and other features of the solar energy system are listed below.

System I/O:

Variable
Description
Input/Output

T_p
Temperature at the top of the panels
Input (Resistance)

T_f
Temperature in the flow from
Input (Voltage)

exchanger to panels

T_s
Temperature at the top of solar storage
Input (Resistance)

tank

T_L
Lower Sensor in Evolution Tank
Input (Resistance)

(Currently Exist)

T_U
Upper Sensor in Evolution Tank
Input (Resistance)

(Currently Exist)

Flow
Flow of the heat transfer fluid
Input (Voltage)

T_t
Temperature on surface mount sensor on
Input (Resistance)

the tank

Pump
Pump speed based on T_p-T_t
Output (Voltage)

Display:

S
U
P
P
L
Y
X
X
X
°
F.

S
O
L
A
R

R
E
T
U
R
N
X
X
X
°
F.
P
U
M
P

O
N

Supply XXX ° F. = Temperature at Panels (T_p)

Return XXX ° F. = Temperature at flow Meter (T_f)

Pump On-When Solar Pump is running. Pump Off-When Solar pump is not running

X
X
.
X

G
P
M

S
O
L
A
R

X
X
X
X
X
X

B
T
U
P
U
M
P

X
X
X
%

XX.X GPM = Amount of flow measured from flow meter (Flow)

XXXXXX BTU- Indicates the amount of BTU gain per day based on (T_p− T_f) and flow.

Reset at midnight each day.

Pump XXX %- Is the percentage of pump speed to the variable speed solar pump (0-

100%).

P
A
N
E
L

X
X
X
°
F.
S
O
L
A
R

T
A
N
K

X
X
X
°
F.

Panel XXX ° F. = Temperature at the panel (T_p)

Tank XXX ° F. = Temperature of surface mounted tank temperature sensor (T_t)

X
X
X
%
S
O
L
A
R
S
O
L
A
R

X
X
X
%
F
U
E
L

XXX % Solar- (Total Solar Input/(Total Solar Input − Total Burner Input)) × 100

XXX % Fuel-(Total Burner Input/(Total Solar Input − Total Burner Input)) × 100

1) Add status screen shown below between the current evolution screen 2-3.

M
O
D
U
L
E

P
U
M
P

X
X
X
%

C
H

T
A
R
G
E
T

X
X
X

°
F.

Fault Conditions:

Fault Description
Error Type
Display Message

1)
Pump Boost Never
Solar
No Solar Flow

Achieves Flow
Blocking

2)
Panel Temperature Sensor
Solar
Panel Sensor Fail

Working Improperly
Blocking

3)
Tank Temperature Sensor
Solar
Tank Sol Sensor Fail

Working Improperly
Blocking

4)
Solar Storage Tank Sensor
Solar
Storage Sensor Fail

Working Improperly
Blocking

5)
Upper Tank Sensor Reached
Solar
High Temp Reached

High Limit
Blocking

Program Parameters:
Installer Parameter—Solar ΔT Off—(1-40° F. Default 5° F.)
Installer Parameter—Solar ΔT On—(3-40° F. Default 10° F.)

Note: The “Solar ΔT On” must be a factory parameter (Solar ΔT Offset) above “Solar ΔT Off”

Installer Parameter—Solar Pump Startup Time—(0-100 Min Default 0 Minutes). For drain back systems a value greater than 0 will be entered. If time=0 then no extra time is required to run pump. (During this time the pump will run at full speed.)

Installer Parameter—Pump Anti-Cycle Time—(0-20 Minutes Default 2 Minutes). If Value equal 0=Refer to factory parameter (To avoid relay chatter)

Installer Parameter—NHX Configuration—(Yes/No Default No). If yes next two parameters apply. (See Programming Logic for operation theory.

Installer Parameter—NHX Storage ΔT Off—(1-40° F. Default 0° F.).
Installer Parameter—NHX Storage ΔT On—(3-40° F. Default 0° F.).

Note: The “NHX Storage ΔT On” must be at least 2° F. above “NHX Storage ΔT Off”

Factory Parameters—Solar ΔT Offset—(0-10° F.)-Default 3° F.
Factory Parameters—Min Pump Anti-Cycle Time (0-60 Seconds Defaults 10 Seconds)
Factory Parameters—Solar Pump Low Startup Voltage (0.0-10.0V Default 2 Volts)
Factory Parameters—Solar Pump Low Startup Time (0-120 Sec Default 10 Seconds)
Factory Parameters—Pressurized Solar Pump Minimum (0-10V Default 2 Volts)
Factory Parameters—Pump Boost Start Time (0-30 Min Default 2 Minutes)
Factory Parameters—Pump Boost Percentage (0-100% Default 10%)
Factory Parameters—Pump Boost On Time (0-100 Minutes Default 2 Minutes)
Program Logic:

When: T_p−T_t>“Solar ΔT On” turn pump on Full Speed for “Pump Startup Time”

- If “Pump Startup Time”=0 do not run at full speed.
  
  If “Pump Startup Time”=0 run solar pump at “Solar Pump Low Startup Voltage” for “Solar Pump Low Startup Time”
  
  Then: Control Pump (PID) to control T_pto T_t+“Solar ΔT”
- If “Pump Startup Time”=0 control range (0-10V)
- If “Pump Startup Time”=0 control range (“Pressurized Solar Pump Min”-10V)

Until: 1) T_p−T_t<“Solar ΔT Off”

- 2) T_u>Max Tank Temperature (2AF?)

NHX Configuration:

If “NHX Configuration”=Yes and if T_s−T_L>“NHX Storage ΔT On” run solar circulator pump

- Until: 1) T_s−T_L<NHX Storage ΔT Off”
  - 2) T_u>Max Tank Temperature (2AF?)

When there is voltage supplied to the solar pump, and there has been no flow measured from the flow meter for “Pump boost start time” stop running PID control Logic. Boost pump from its current voltage output by “Pump Boost Percentage” for “Pump Boost on Time”. Continue sequence until flow has been detected. After flow has been detected return to PID Logic. (Note: When converting between control schemes, the pump must continue to run) In HTP Software add BTU Solar In Calculator Based on T_p,T_f, Flow. Values to be stored in the 13 month log file. In HTP Software add a graphics screen to represent Values in 13 month log file. See example at FIG. 7

Referring to FIG. 3, another heating system 30 for controlling the efficiency of a heating system includes a storage container or tank in a closed loop and optional instantaneous direct hot water open loop with firing the burner less frequently. The heating system of FIG. 3 provides fluid isolation using a brazed plate heat exchanger, modulation of energy transfer using variable inputs of the burner assembly and pump, and high efficiency with hydraulic stability by having high efficiency combustion system heating a large mass. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system which may have one or more configurations. The two or more fluid isolated systems in the heating device are capable of modulating the transfer of energy between systems using a heat exchanger while retaining individual system fluid isolation.

The heating system includes a heat exchanger for transferring heat is connected between a primary fluid system providing storage fluid for space heating to an additional secondary fluid system having domestic hot water. Generally, the primary fluid system includes a container for storing fluid in a closed loop with hydraulic stabilization, a heating element, a heating supply structure, a storage fluid pump, a storage fluid circulating pump, temperature sensors, a burner or heating assembly, and a heat exchange pump. The container includes an upper temperature sensor and a lower temperature sensor with a heating element substantially positioned within the storage for increasing a temperature of the heating supply fluid. The container is configured to being a hydraulic stabilizer along with separating contaminants and air from the heating supply fluid or heat transfer fluid. The heating supply structure or radiant heating loop is connected to the container for storing fluid. The storage pump is connected to the heating supply structure and the container for delivering storage fluid to the heating supply structure. As reference through this specification, the pump may be a variable speed pump. The storage fluid circulating pump is connected to the heating supply structure used for circulating heating supply fluid through the heating supply structure and back to the container. A first temperature sensor is connected to the heating supply structure for measuring the temperature of the storage fluid within the heating supply structure. A heat exchange pump is provided for delivering heating supply fluid from the container to the heat exchanger. A second temperature sensor is connected between the heat exchanger and the container to measure the temperature of the storage fluid.

The additional secondary fluid system may include an inlet for DHW fluid connected to the heat exchanger, a temperature sensor connected between the inlet and the heat exchanger to measure the temperature of the DHW fluid entering through the inlet, a flow sensor for measuring the flow of DHW fluid exiting the heat exchanger, a temperature sensor for measuring the temperature of the DHW fluid exiting the heat exchanger, and an DHW outlet for DHW fluid connected to the heat exchanger.

In operation, the system of FIG. 3, operates to control the efficiency of the heating system. To achieve a set storage fluid temperature, the burner assembly will fire to deliver heat through the heating element which will increase the temperature of the storage fluid. If a demand for domestic hot water is received by a controller, the controller will activate the pump to deliver storage fluid to a heat exchanger where heat is transferred to a domestic hot water and exited out of the DHW outlet. If a demand for space heating is received by a controller, the controller will activate a pump to directly deliver heated storage fluid to the radiant heating loop. The storage fluid will then, in turn, circulate through an external radiant heating loop through the system inlets and outlets. Throughout the operation of this heating device, temperature sensors for the storage fluid and domestic hot water will monitor and send feedback to the controller to process and calculate the desired temperature set points for the storage fluid and domestic hot water which can be modulated by operating pumps to deliver storage fluid to the heat exchanger at a defined flow rate and temperature to increase the temperature of the domestic hot water.

Another method for controlling efficiency of a heating system includes the following steps as outlined herein. The method provides for continuous control for optimum system efficiency. Initially, the default settings for the heating system are set for the radiant supply temperature set point (Rsp), the delta T(Rdif), and the minimum outdoor design temperature when the system is initially configured. Of course, the domestic hot water temperature and the warm weather shut down temperature may be adjusted after initial settings. From those parameters and other factory parameters, the storage fluid within the storage container will be calculated to adjust based upon an outdoor temperature. The colder the outdoor temperature, the higher the storage fluid temperature set point. Preferably, the storage fluid temperature will adjust up to a factory parameter set high limit.

To summarize, the added control inputs are radiant supply temperature sensor, heat exchanger supply temperature, and heat exchanger return temperature and the added control outputs are the radiant module pump voltage (0-10 volts). An outlined of sample of the initial parameters are listed below.

User Parameters (In Radiant Mode)

Default

Input Name
Description
Range
Set Point

Desired
Sets tank temperature set point
80-140° F.
110° F.

DHW
in summer mode at the top sensor

Temperature

DHW
Differential from “Desired DHW
1-30° F.
7° F.

Differential
Temperature” at the top sensor

when the burner is activated

Warm
Sets at which outdoor
32-95° F.
68° F.

Weather
temperature the central heating

Shut Down
mode is disabled.

Installer Parameters (In Radiant Mode)

Default

Input Name
Description
Range
Set Point

Radiant Supply
Radiant Supply
50-140° F.
120° F.

Temperature Set Point
Temperature Required

(Rsp)
at minimum outdoor

design temperature

Radiant Temperature
Radiant Temperature
1-30° F.
20° F.

Differential-Delta T
differential required

(Rdif)

Minimum Outdoor
The minimum outdoor
−49-32° F.
5° F.

Design Temperature
temperature used to

design the system

Factory Parameters (In Radiant Model

Default

Input Name
Description
Range
Set Point

Tank Temperature
Restricts the tanks temperature set
80-180° F.
TBD

High Limit
point to not exceed a determined value

Pump Fault Run Time
How long the pump will run without
0-? Sec
45 Sec

seeing the temperature on the current

heat exchanger return being to rise

Pump Fault Minimum
The rate of change required on the
0-10° F./sec
1° F./sec

Rise
“heat exchanger return sensor” in

“Pump Fault Run Time”. Otherwise

indicate pump fault.

Radiant Pump Start
A percentage of the (0-10 V) to start the
0-100%
50%

Percentage
pump and initiate flow before starting

PID control

Radiant Pump Start
The amount of time the Radiant pump
0-60
10 Sec

Time
is run at “Radiant Pump Start Time”

through start up to obtain enough flow

through the exchanger to start PID

control

Supply Increase Rate
The minimum increase in supply
0-10° F./Sec
1° F./Sec

Minimum
temperature beyond which the tank

temperature boost is activated

Pump High Voltage
The length of time the pump will run at
0-? Sec
60 Sec

Run Time
10 V without reaching supply

temperature until the tank temperature

boost is activated

Tank Temperature
The offset below the “Radiant Supply
0-20° F.
5° F.

Boost Offset
Set Point” that must be reached before

tank temperature boost is activated

Tank Temperature
Increases current tank temperature set
0-50%
8%

Boost Percentage
point by this percentage if the time

exceeds the “Pump High Voltage Run

Time”, and the supply temperature

increase rate is below the “Supply

Increase Rate Minimum” without the

radiant supply temperature reaching the

“Tank Temperature Boost Offset”

below the “Radiant Supply

Temperature Set Point.”

Tank Temperature
The amount of voltage the pump must
0-10 V
0 V

Boost Reset
reach to reset the tank temperature

original calculated set point

Percentage Delta T
A percent of the installer input “Delta
0-150%
100%

Tank Temperature
T” that the tank temperature will be

Offset
offset above the “Radiant Supply Set

Point”

Radiant Loop Run
Amount of time after CH Pump start, to
0-120
30

Time
start the Radiant Module Pump
Seconds
Seconds

Tank temperature set point to be set to a calculated value based on but not below the DHW setpoint temperature:

Radiant Supply Temperature

Radiant Delta T

Percentage of Delta T Offset

Minimum Outdoor Design Temperature

Warm Weather Shut Down

Outdoor Temperature

$Tank Temp = \frac{Rdif \times % Delta T Tank Temperature Offset / 100}{Min Outdoor Design Temp - Warm Weather Shut down} \times Outdoor Temp + Rsp + Rdif - \frac{Rdif \times % Delta T Tank Temperature Offset / 100}{Min Outdoor Design Temp - Warm Weather Shut down} \times Warm Weather Shut Down$

EXAMPLE

Setting

User Parameters

Mode Change Temperature
60

Desired DHW Temperature
100

Installer Parameters

Minimum Outdoor Design Temperature
−5

Supply Temperature
150

Delta T
25

Hysteresis
10

Factory Parameters

Tank Temperature High Limit
170

Referring to FIG. 8, the heating system is provided which is capable of adjusting a temperature of storage fluid and radiant supply fluid. The temperature of the storage fluid is measured and has an initial temperature setting. The internal temperature of the storage fluid is adjusted if an external temperature is above warm weather shutdown temperature. If external temperature is below warm weather shutdown temperature, the internal temperature of the storage fluid is adjusted.

Referring to FIG. 9, the method for controlling the efficiency of a heating system further includes controlling a temperature of a radiant supply fluid of the heating system. Generally, the temperature of the radiant supply fluid and storage fluid is measured. The temperature of the radiant supply fluid is compared with the temperature of the storage fluid. The temperature of the radiant supply fluid is increased to a radiant supply temperature set point by increasing flow rate of storage fluid having a higher temperature to heat exchanger. In addition, the temperature of the storage fluid is increased if storage fluid temperature is below the radiant supply temperature.

The radiant supply fluid temperature will be controlled using a radiant supply temperature sensor and a pump that is modulated by a 0-10 volt signal, which may be increased or decreased, which is controlled via a PID (proportional-integral-derivative) loop. If the pump is at full speed and the radiant supply fluid temperature is not increasing fast enough and/or does not come to the radiant supply temperature set point, the storage fluid temperature set point is increased by a specific percentage, thus firing the burner higher. This allows the system to react quickly to a high demand, while still modulating the pump and burner as illustrated in FIG. 9.

The controlling of the radiant supply temperature of the heating system may include the following additional steps. First, demand is initiated by closing TT contacts. Next, central heating (CH) contacts close and central heating (Ch) pump runs for time to be sure radiant heating loop fluid temperature is lower than storage fluid within storage tank or container. If radiant heating loop is cooler than upper sensor of container, the radiant module pump is started. Next, radiant module pump speed is at Radiant Pump Start Percentage for Radiant Pump Start Time. Pump voltage output is varied 0-10V to control radiant supply temperature measured at the radiant supply sensor to the installer parameter “Radiant Supply Temperature Set Point” via (PID) control. The “Tank Temperature Boost Percentage” will become activated if the radiant module pump runs at 10 volts for longer than the “Pump High Voltage Run Time”, and/or the supply temperature increase rate is below the “Supply Increase Rate Minimum” without the radiant supply temperature reaching the “Tank Temperature Boost Hysteresis” below the “Radiant Supply Temperature Set Point.” The tank temperature set point will be restored back to its original set point calculation when the pump voltage is less than or equal to “Tank Temperature Boost Reset.” During this entire cycle, if the top tank sensor falls below (radiant supply temperature+radiant supply differential modified by outdoor reset curve) the burner will then fire.

Referring to FIGS. 10-12, an additional method for controlling or programming the efficiency of a heating system is illustrated for controlling temperature of the storage fluid based upon the inlet water temperature. This method may be used with heating system outlined in FIG. 3 but of course may be adapted for usage in any of the systems outlined herein. This method provides for continuous control for optimum system efficiency. Each line chart provides storage fluid set points relative to inlet temperature of fluid or domestic hot water including summer mode (FIG. 10), winter mode (FIG. 11). Initially, the default settings for the heating system are set for the radiant supply temperature set point (Rsp), the delta T(Rdif), and the minimum outdoor design temperature when the system is initially configured. Of course, the domestic hot water temperature and the warm weather shut down temperature may be adjusted after initial settings. From those parameters and other factory parameters, the storage fluid temperature (summer mode) will be calculated to adjust based on inlet water temperature. In winter mode, the storage fluid temperature will be calculated similarly but it is preferable that the temperature not dip below the radiant supply temperature. The colder the inlet domestic hot water temperature, the higher the storage fluid set point. Of course, the storage fluid temperature will stay below or at a factory parameter set high limit. To summarize, the added control inputs are DHW outlet flow/temperature or vortex meter, DHW inlet temperature, and a heat exchanger return temperature. The added control outputs are DHOW module pump (0 to 10 volts) and a variable speed radiant pump. An outline sample of the initial parameters is listed below.

User Parameters (In Radiant Mode)

Default

Input Name
Description
Range
Set Point

Desired DHW
Sets DHW outlet set point
80-140° F.
110° F.

Temperature

Warm Weather Shut
Sets at which outdoor
32-95° F.
68° F.

Down
temperature the central

heating mode is disabled.

Installer Parameters (In Radiant Mode)

Default

Input Name
Description
Range
Set Point

Radiant Supply
Radiant Supply Temperature
50-140° F.
120° F.

Temperature
Required at minimum outdoor

Set Point (Rsp)
design temperature (I9)

Radiant
Radiant Temperature
1-30° F.
20° F.

Temperature
differential required

Differential-

Delta T

(Rdif)

Minimum
The minimum outdoor
−49-32° F.
5° F.

Outdoor
temperature used to

Design
design the system (I8)

Temperature

Maximum
Outdoor Temperature at

Outdoor
which set-point will stop

Temperature
dropping (I10)

Minimum
Lower radiant temperature

Radiant
set-point which is attained at

Temperature
maximum outdoor

temperature (I11)

Factory Parameters (In Radiant Mode)

Default

Input Name
Description
Range
Set Point

Tank
Restricts the tanks temperature
80-180° F.
TBD

Temperature
set point to not

High Limit
exceed a determined value

Pump Fault
How long the pump will run
0-? Sec
45 Sec

Run Time
without seeing the temperature

on the current heat exchanger

return being to rise

Pump Fault
The rate of change required on
0-10° F./sec
1° F./sec

Minimum
the “heat exchanger return

Rise
sensor” in “Pump Fault Run

Time”. Otherwise indicate

pump fault.

DHW Pump
A percentage of the (0-10 V) to
0-100%
50%

Start
start the pump and initiate flow

Percentage
before starting PID control

DHW Pump
The amount of time the Radiant
0-60
10 Sec

Start Time
pump is run at “Radiant Pump

Start Time” through start up to

obtain enough flow through the

exchanger to start PID control

The following is the DHW mode logic as outlined below. First the DHW inlet temperature is stored. When the DHW flow (from vortex meter) drops below “DHW inlet flow temperature storage,” store the last DHW inlet temperature (DHWs) before the flow dropped below “DHW inlet flow temperature storage”. This stored value will be used to calculate the tank temperature set point when the tank is at rest. Next the tank temperature is set based upon a summer or low setting where outdoor temperature is above “Warm Weather Shut Down” parameter. The tank temperature set point is calculated using DHW output and last recorded DHW inlet temperature. Therefore calculate tank temperature is calculate as follows: Tank Temperature=DHW outlet set point+(DHW outlet set point−DHWs)

If winter or high setting where outdoor temperature is below “Warm Weather Shut Down” parameter, the tank temperature set point is calculated using DHW output and last recorded DHW inlet temperature. But the tank temperature set point shall not drop below the “Radiant Supply Set Point” other wise use same calculation as summer mode as calculated: Tank Temperature=DHW outlet set point+(DHW outlet set point−DHWs).

EXAMPLE

In addition, FIG. 12 illustrates the relation between the storage fluid set points within a storage container relative to the inlet temperature of fluid or domestic hot water with a pump modulating range and a tank temperature boosting range. Referring to FIG. 12, the domestic hot water temperature (DHW) is controlled via DHW outlet temperature and flow, DHW inlet temperature and a DHW module pump that is modulated by a 0-10 volt signal which is controlled via a PID loop. If the pump is at full speed and the DHW outlet temperature is not increasing fast enough and/or does not come to the DHW outlet temperature set point, the storage fluid set point is increased by a specific percentage, thus firing the burner higher. This allows the system to react quickly to a high demand, while still modulating the pump and burner. The tank temperature boost will reset back to its original calculated setting once the DHW module pump voltage falls below a set point, or storage fluid reaches its high limit.

The following outlines the method for controlling DHW Supply Temperature. Demand is initiated by DHW outlet temperature dropping below “DHW Supply Set Point” when there is a flow reading on the DHW outlet flow (vortex meter). DHW module pump runs at speed at “DHW Pump Start Percentage” for “DHW Pump Start Time”. DHW Pump voltage output is varied 0-10V to control DHW supply temperature measured at the DHW supply sensor to the installer parameter “DHW Supply Temperature Set Point” via (PID) control. The “Tank Temperature Boost Percentage” will become activated if the DHW module pump runs at 10 volts for longer than the “Pump High Voltage Run Time”, and/or the DHW outlet temperature increase rate is below the “Supply Increase Rate Minimum” without the DHW supply temperature reaching the “Tank Temperature Boost Hysteresis” below the “DHW Supply Temperature Set Point.” The tank temperature set point will be restored back to its original set point calculation when the DHW pump voltage is less than or equal to “Tank Temperature Boost Reset.” During this entire cycle, if the top tank sensor falls below calculated tank temperature set point the burner will fire

FIGS. 13-23 illustrate an alternative heating device which is capable of providing a hot water supply and space heating which provides two or more isolated fluid systems with a heat exchange modulating heat transfer between the two or more isolated fluid systems similar to the embodiments outlined above. This alternative heating device has multiple configurations for providing hot water supply and space heating including optional heat packs or modules for domestic hot water and space heating that can be connected to a base design.

Referring to FIG. 13, the alternative heating device 100 includes the following features: Low Water Cutoff 101—which assures that the tank will not operate unless it is filled with water; Hot Water Outlet 102—dip tube draws all the hot water from the top of the tank near the domes. Improved amount of hot water delivery from tank; High Limit Safety 103; Upper Temperature Sensor 104—accurately measures temperatures to control burner input; Heat Pack (Optional Supply Connection) 105 dip tube insures that hot water supply to the Heat Pack; Heat Pack (Optional) Return Connection 106 drop tube insures cooler water is returned from the Heat Pack to the lower portion of the tank; Digital Text Display 107 for system monitoring and temperature adjustment; Lower Temperature Sensor 108 accurately measures to control burner input; Cold Water Inlet 109—bottom feed cold water to help remove sediment from bottom of tank; Air Vent Acces 110—for closed loop systems (SS Gal. Models only); Temperature and Pressure Relief Valve—120; Auxiliary Connection—111; 316 L Stainless Steel Construction—112; 2″ Foam Insulation 114—½ degree per hour heat loss; Plastic Outer Jacket 113—will not rust! Dent resistant; Combustion Heat Exchanger 115—Stainless Steel/Cupronickel; Modulating Burner Assembly 116—3 to 1 Turndown; Intake Connection 117—easy installation with PVC Plastic Pipe; Auxiliary Connection 119; Exhaust Connection 118—easy installation with PVC Plastic Pipe; and Condensate Connection 120.

Referring to FIG. 14, the alternative heating device includes the following features: DHW inlet; Grundfos Vortex Meter—accurately measures temperature and flow for precisions control; Isolation Valve; Brazed Plate Heat Exchanger; BSP Union with washer seal for easy maintenance; Barrel Nuts—supports for easy installation; First and Second Isolation Valves; Curved Black Plate—matches tank surface for strength and clean look; Pressure Relief Valve; Isolation Valve; Variable Speed Pump—allows for modulating flow from tank to accurately control supply temperature; Brackets allows for easy maintenance; and BSP Union with wash seal for easy maintenance.

Referring to FIG. 15, the alternative heating device includes the following features: System Supply; System Return; Temperature Sensor accurately measures temperature for precision control; First and Second Isolation Valves; Brazed Plate Heat Exchanger; BSP Union with Washer Seal for easy maintenance; Barrel Nuts supports for easy installation; BSP Union with Wash Seal for easy installation and maintenance; Third Isolation Valve; Variable Speed Pump—allows for modulating flow from tank to accurately control supply temperature. Bracket allows for easy maintenance; Fourth Isolation Valve; Pressure Relief Valve; Curved Black Plate—matches tank surface for strength and clean look; and System Feed.

Referring to FIGS. 16A-16B, the alternative heating device includes the following features: Left Side (low water cutoff, hot water outlet, high limit safety, upper temp sensor, lower temp sensor, electrical connections, cold water inlet) and Right Side (temp/pressure relief valve, auxiliary connection, condensate drain, second auxiliary connection).

Referring to FIG. 17, the alternative heating device includes the following features: Gas line; heat pack (optional); air intake; and exhaust vent.

Referring to FIG. 20, the alternative heating device includes the following features: High Limit Safety Switch; Low Water Cut-off assures that the tank will not operate unless it is filled with water; Upper Temperature Sensor—accurately measures temperatures to control burner input; Heat Pack (Optional) Supply Connection—dip tube insure hot water supply to the Heat Pack; Heat Pack (Optional) Return Connection—dip tube insures cooler water is returned from the Heat Pack to the lower portion of the tank; Digital Text Display for system monitoring and temperature adjustment; Lower Temperature Sensor—accurately measures temperatures to control burner input; Solar Control Well; Cold Water Inlet—bottom feed cold water to help remove sediment from bottom of tank; Temperature and Pressure Relief Valve; Auxiliary Connection; 316 L Stainless Steel Construction; 2″Foam Insulation—½ per hour heat loss; Plastic Outer Jack—will not rust, dent resistant; Combustion Heat Exchanger—stainless steel/cupronickel; Intake Connection—easy installation with PVC Plastic Pipe; Auxiliary Connection; Exhaust Connection—easy installation with PVC Plastic Pipe; Condensate Connection; Modulating Burner Assembly 3 to 1 Turndown; and Solar Heat Exchanger.

Referring to FIGS. 23A (left side) 23B (front) and 23C (right side), the alternative heating device includes the following features: Left Side (low water cut-off, high limit safety, hot water outlet, upper temp sensor, lower temp sensor, electrical connections, control well, cold water inlet); Front (heat pack—optional, air intake, exhaust vent, gas line); and Right Side (auxiliary connection, temp/pressure relief valve, condensate drain, and auxiliary connection).

The method and systems for controlling the efficiency of the heating system above may further include additional features. A fault may be used to detect an air lock or flow blockage to determine if heat exchanger needs servicing. If the Heat Exchange Return Temperature doesn't reach a “Pump Fault Minimum Rise” within “Pump Fault Run Time”, the pump will be shut down and display a Fault on the screen. The pump is only allowed to run if the top tank temperature sensor is above the “Radiant Supply Temperature” for DHW Priority/Radiant Latent Heat Preservation feature. Oftentimes, the variable speed radiant pump is not run when the DHW module pump is running over 50%. A domestic hot water (DHW) preferential or radient latent heat preservation may be used to control priority between the hot water supply and space heating demands. This preferential allows the radiant loop pump to run for “Radiant Loop Run Time”, if the temperature on the “Radiant Supply Temperature Sensor” is above the current top sensor, do not run the radiant module pump. The radiant module pump is allowed to run once the top tank temperature sensor as gone above the “Radiant Temperature Differential” above “Radiant Supply Temperature Set Point.” This will allow for the tank temperature to always remain above the DHW set point. It will also avoid running colder water through the radiant system thus removing any latent heat that may remain in the system. A BTU loss pre-fire may be used to predict high heating demand.

A pump control may be used that is manually operated. It provides an ability to manually override both CH and radiant module pump. Speed of radiant module pump will be controlled manually in this mode as well. An overall monitoring system may be added to monitor and regulate the energy usage by the heating system. The heating system may have a delivered energy to radiant which is an ability to calculate BTU's delivered to the radiant system using the top tank sensor as the heat exchanger return sensor, as well as the pump voltage (flow) that will determine the amount of energy delivered to the radiant system. Also, the delivery energy to the DHW is calculated by BTU's delivered to the DHW system using the vertex meter for outlet temperature and flow, and the DHW inlet temperature from which it can determine the amount of energy delivered to the DHW.

If the difference in temperature between the tank top sensor and the Heat Exchanger Return Temperature is too low for a given pump voltage. Display will give a warning that heat exchanger will need to be cleaned or serviced (blocking code). Zone Control 1025 set point from 1025 will override “Radiant Supply Temperature Set Point” installer menu. 1025 outdoor sensor will replace the 926 outdoor sensor. The heating systems above may be used in connection with various applications including hydronic baseboard, radiant, and hydro-air systems.

It is therefore an object of the present invention to provide a method and system for controlling the efficiency of the heating system. The heating system is a combination hot water supply and space heating system that can modulate energy transferred between the hot water supply and space heating system which may have one or more configurations. The heating system demonstrates fluid isolated systems in a heating device. The two or more fluid isolated systems in the heating device are capable of modulating the transfer of energy between systems using a heat exchanger while retaining individual system fluid isolation

It would be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be covered by the appended claims and the present invention.

METHOD AND SYSTEM FOR CONTROLLING EFFICIENCY OF HEATING SYSTEM

Information

Publication Number

Date Filed

Date Published

Inventors

Original Assignees

CPC

US Classifications

International Classifications

Abstract

Description

Claims

CROSS-REFERENCE TO RELATED APPLICATION

Provisional Applications (1)