AIR HEATING AND POTABLE WATER SYSTEM HAVING A WATER HEATER AND A HYDRONIC AIR HANDLER

Abstract

Air heating and potable water systems have a thermostat with a computer processing unit (CPU), a hot water heater, a hydronic air handler, and a primary pump controlling flow of hot water from the water heater into the hydronic air handler, which has a hydronic coil, a blower, and a first control panel having a CPU in operative communicates with the thermostat. The hydronic coil receives hot water from the water heater to warm air passing over the hydronic coil. The primary pump is in operative communication with the first control panel and an indicator of hot water flow. The indicator of hot water flow is in operative communication with either the thermostat or the first control panel, and any CPU in the system stores a priority instruction, which upon an indication of hot water flow deactivates or delays activation of the primary pump for a predetermined period of time.

Description

TECHNICAL FIELD

The invention relates to an air heating and potable water system, more particularly, an air heating and potable water system having a water heater, which can be tankless, in fluid communication with a hydronic air handler, a sensor sensing flow in a building's hot water supply, and a thermostat in communication with the sensor and the hydronic air handler to delay activation of the hydronic air handler during use of hot water within the building.

BACKGROUND

In the heating and cooling industry, there are many ways of heating/cooling air for domestic and commercial buildings. The traditional method is a furnace and air conditioning system. With the increase in demand for “on-demand” tankless hot water heaters, there has been recognition that the tankless hot water heater can also assist in heating air rather than requiring a traditional furnace. An air handler in conjunction with the tankless hot water heater can serve this function. The tankless water heater supplies hot water to the air handler to generate heated air. Such a system must balance the demand for heated air with the demand for heated water for use by sinks, dishwashers, showers, etc. There is a need for improvements in tankless hot water heater-air handler systems regarding how the demand for the heated water is controlled.

For buildings utilizing an air handler-heat pump combination for heat, there is a significant electricity cost in running this combination in climates that have a long cold season or a colder season based on temperatures, such as in the north and northeastern parts of the U.S. and Canada. An air handler-heat pump combination does not include a hydronic coil. Rather, the air handler includes an electric heating element to generate heat when the heat pump is unable to meet the demand. The electric heating element energizes when a sensor within the air handler reads a lower supply air temperature than the setpoint demand. The electric heating element compensates to raise the air temperature to the setpoint demand. An electric heating element draws a large amount of electricity and will greatly affect the electric bill for the building, i.e., making the bill higher. There is a need to modify these air handler-heat pump combination systems to provide an alternate air heating method to compensate for the heat pump when it cannot meet the setpoint demand that is more energy efficient.

SUMMARY

In all aspects, air heating and potable water systems for buildings are described herein. These systems have a thermostat having a computer processing unit with nontransitory memory comprising a heating instruction, a hot water heater, a hydronic air handler having a hydronic coil, a blower, and a first control panel having a computer processing unit with nontransitory memory. The hot water heater has a water heater control panel having a computer processing unit with nontransitory memory. The first control panel is in operative communication with the thermostat, and the hydronic coil is in fluid communication with the hot water heater and receives hot water from the hot water heater to warm air passing over the hydronic coil. The system also has a primary pump controlling fluid communication of hot water from the hot water heater to the hydronic coil and is in operative communication with the first control panel. The system has an indicator of hot water supply usage within the building and in operative communication with either the thermostat or the first control panel. Either the computer processing unit of the thermostat, the first control panel, or the water heater control panel stores a priority instruction, which upon an indication of hot water flow to the hot water supply of the building from the sensor deactivates or delays activation of the primary pump by a predetermined period of time. The priority instruction is configured to send a signal to the hot water heater to activate the hot water heater, which provides hot water to the hot water supply of the building while the primary pump is deactivated or delayed for the predetermined period of time.

The hot water heater can be a tankless gas or electric hot water heater, a hydrogen eater splitting hot water heater, or a Peltier thermoelectric hot water heater.

In all aspects, the thermostat can be in direct electrical communication or has a wireless communication with the control panel of the hydronic air handler. The primary pump can be external to the hydronic air handler. The indicator of hot water supply usage within the building is a pressure sensor or a fluid flow sensor compatible with potable water positioned in the hot water supply of the building, is the hot water heater control panel, or the thermostat. The sensor can be a differential pressure sensor, which can be an absolute pressure sensor or a gauge pressure sensor. The predetermined period of time is selected from the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30 minutes or is equivalent to the minutes for a cycle of an appliance within the building that uses hot water.

In all aspects, the first control panel or the thermostat stores a first blower instruction in the computer processing unit thereof to continue activation of the blower and primary pump for a post-heat period of time; wherein, after a setpoint demand for heat has been reached, the blower instruction signals the blower and the primary pump to continue activation thereof for the post-heat period of time to utilize residual heat stored in any of the components in the system. The first control panel or the thermostat stores a second blower instruction in the computer processing unit thereof to run the blower at a reduced rate when there is no call for air-conditioning or heating for a ventilation period of time.

The systems can further comprise a heat pump positioned exterior to the building, an indicator of outdoor ambient air temperature, an evaporator coil within the interior of the building in fluid communication with a condenser of the heat pump and the evaporator coil is in fluid communication with the blower of the hydronic air handler for passing air over the evaporator coil. The heat pump includes the condenser, a refrigerant within the condenser, a compressor, a second control panel having a computer processing unit with nontransitory memory, and a reversing valve. The thermostat is in operative communication with the second control panel and has a cooling instruction for activating the heat pump to provide air conditioning to the building. Either the computer processing unit of the thermostat, the first control panel, or the second control panel stores a reversing instruction, which upon an indication of outdoor ambient air temperature being warmer than a predetermined set point temperature and a call for heat, activates the reversing valve of the heat pump to send heated refrigerant to the evaporator coil to heat air passing over the evaporator coil and the first control panel keeps the primary pump deactivated. The indicator of ambient air temperature is a temperature sensor at the exterior of the building in operative communication with the thermostat or is a temperature algorithm stored in nontransitory memory of the thermostat that is configured to monitor cycle times and operation times of the heat pump to simulate outdoor air temperature and calculate when the heat pump or the hydronic air handler acts as primary heat source. The temperature sensor is a sensor positioned to sense ambient air temperature at the exterior of the building or is a digital source in electrical communication with the thermostat.

In another aspect, a hydronic kit for an air handler-heat pump system of a building with a hot water generating system is disclosed. The kit includes a hydronic coil, a primary pump configured to be connected in fluid communication with the hydronic coil to pump hot water into the hydronic coil and in fluid communication with hot water from a hot water generating system, a control interface circuit having a computer processing unit with nontransitory memory connectable to a control panel of an air handler-heat pump system and configured to control activation of a blower of the air handler-heat pump system and configured to receive an indication of hot water supply usage within the building, and a wiring harness configured to connect the primary pump and the hot water generating system to the control panel of the air handler-heat pump system. The control interface circuit stores a priority instruction that upon an receipt of an indication of hot water supply usage within the building, a deactivation or delay activation signal is sent to the primary pump to deactivate or delay activation for a predetermined period of time. In one embodiment, the deactivation or delay activation signal is sent from a thermostat in the building to the primary pump.

In one embodiment, the indication of hot water supply usage is received from a sensor included in the kit that is positionable to determine flow of hot water in a hot water supply of a building and configured for operative communication with the control interface circuit, the thermostat, and/or the control panel of the air handler-heat pump system. In all aspects of the kit, the sensor is a pressure sensor or a fluid flow sensor and is compatible with potable water, such as a differential pressure sensor, which can be an absolute pressure sensor or a gauge pressure sensor. The predetermined period of time is selected from the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30 minutes or is equivalent to the minutes for a cycle of an appliance within the building that uses hot water. The control interface circuit is configured for switching between hydronic heating-heat pump mode and air handler-heat pump mode.

In all aspects, the kit can further include an indicator of outdoor ambient air temperature. The control interface circuit stores a reversing instruction, upon an indication of outdoor ambient air temperature being warmer than a predetermined set point temperature and a call for heat, configured to activate a reversing valve of the heat pump to send heated refrigerant to the evaporator coil to heat air passing over the evaporator coil and the control interface circuit keeps the primary pump deactivated. The indicator of ambient air temperature is a temperature sensor at the exterior of the building in operative communication with the thermostat, is a digital source in electrical communication with the thermostat or the control circuit interface, or is a temperature algorithm stored in nontransitory memory of the thermostat that is configured to monitor cycle times and operation times of the heat pump to simulate outdoor air temperature and calculate when the heat pump or the hydronic air handler acts as primary heat source.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of an air heating and potable water system.

FIG. 2 is one example of the duct work connection to the hydronic air handler unit of the system of FIG. 1.

FIG. 3 is a front perspective view of a hydronic air handler with its front cover removed.

FIG. 4 is an exploded view of the hydronic air handler of FIG. 3.

FIG. 5 is an exterior building view of the heat pump unit in FIG. 1.

FIG. 6 is a side perspective view of a heat pump with its front and top removed.

FIG. 7 is a partial exploded view of the heat pump unit in FIG. 6.

FIG. 8 is a schematic representation of the communication between the heat pump and the evaporator coil.

FIG. 9 is a schematic of an air handler-heat pump heating system retrofitted to have a hydronic kit to heat the building in the colder season.

DETAILED DESCRIPTION

The following detailed description will illustrate the general principles of the invention, examples of which are additionally illustrated in the accompanying drawings. In the drawings, like reference numbers indicate identical or functionally similar elements.

Referring to FIG. 1, an air heating and potable water system of a building, referred to by the reference 100, is shown schematically to include a thermostat 102, a tankless hot water heater 104, a hydronic air handler 106, an evaporator coil 108 (shown as an A-coil), a heat pump 110, and a primary pump 112. The system of FIGS. 1-3 is an open heat transfer system because the water in the system is constantly changing as the potable water is used for other household or building uses, such as toilets, sinks, showers, baths, or by dish washers, washing machines, etc. The heat pump 110 is positioned exterior to a wall 114 of the building and the other units are in the interior of the building. The tankless hot water heater 104 has a gas supply line (G) in fluid communication with a gas inlet 118 in FIG. 1, but is not limited thereto as the means to heat the water. In other embodiments, the tankless hot water heater could be an electrical unit or an alternate energy source such as hydrogen or photo voltaic. The tankless hot water heater can be any commercially available unit or hereinafter developed unit. The tankless hot water heater 104 has a water inlet 120 receiving the water supply and a water outlet 122 for the heated water. Each of these inlets and outlets can have universal fittings for installation and replacement purposes. Further, each conduit/piping leading therefrom can include a manual shot off valve 124 and/or a manual drain 126. The tankless hot water heater can include a condensate drain line if needed. The tankless hot water heater 104 has its water outlet 122 in fluid communication with the building hot water supply 130, which can include a mixing valve 128 receiving cold water, and in fluid communication with the primary pump 112 that pumps hot water into the hydronic air handler 106. The system can include check valves 142 positioned as needed, such as in the cold water supply and the water return from the hydronic air handler shown in FIG. 1.

While a tankless hot water heater is illustrated in FIG. 1, in particular, a tankless gas hot water heater, the invention is not limited thereto. In one embodiment, the hot water heater can be an electric tankless hot water heater. In another embodiment, the hot water heater can be a Peltier element hot water heater. In yet another embodiment, the hot water heater can be a carbon zero hot water heater, i.e., any commercially available or herein after developed electric hot water heater. One specific example of a carbon zero hot water heater is a HYDRO ZERO™ tankless hot water heater, which utilizes the energy from splitting water into hydrogen and oxygen in a plasma state, made by Hydro Zero of Union Bridge Works, Roker Lane, Pudsey, Leeds, LS28 9LE and available in North America from Carbon Zero Solutions, Ltd. of Vancouver, BC, Canada.

The system can include an expansion tank 144. In FIG. 1, the expansion tank 144 is in fluid communication with the cold water supply. Turning now to FIG. 2, the housing 109 for the evaporator coil 108 is seated on top of the hydronic air handler 106 and is in fluid communication with the blower of the hydronic air handler for the passage of air over and through the evaporator coil. In fluid communication with and above the housing 109 of the evaporator coil 108 is a duct branch 146 having a plurality of dampers 148 controlling air flow through the ducts 150 leading to different rooms or spaces with the building. Also shown in FIG. 2 is the air return duct 152 returning air to the blower section of the hydronic air handler 106.

The primary pump 112 controls the fluid communication of the hot water from the tankless hot water heater 102 into the hydronic air handler 106. In FIGS. 1 and 2, the primary pump 112 is positioned external to but most proximate the hydronic air handler 106. However, as represented by the dashed box 140 within the hydronic air handler 106, the primary pump may be within the interior of the housing of the hydronic air handler.

The system 100 includes a sensor 132, also referred to herein as a priority switch, positioned to determine flow of hot water into the building's hot water supply 130. The sensor or priority switch 132 can be any suitable sensor that is compatible and safe for use with hot potable water. The sensor 132 can be a pressure sensor or a fluid flow sensor. If a pressure sensor is selected, the sensor can be an absolute pressure sensor, a differential pressure sensor, or a gauge pressure sensor. In one embodiment, the pressure sensor is a differential pressure sensor. The sensor 132 is in operative communication with the thermostat 102, first control panel 116 of the hydronic air handler 106, and/or the third control panel 136 of the tankless hot water heater 104.

The thermostat 102 is in operative communication with (i) the hydronic air handler 106, more particularly with a first control panel 116 thereof, and/or (ii) the heat pump 110, more particularly with a second control panel 134 thereof, and optionally with (iii) the sensor 132. The first control panel 116 of the hydronic air handler 106 is in operative communication with the thermostat 102, the primary pump 112, the second control panel 134 of the heat pump 110, and optionally with the sensor 132 and optionally with a third control panel 136 of the tankless hot water heater 104. The operative communications within the system 100 (represented by the dashed lines in FIG. 1) can be electrical or other types of wired direct communications or may be any type of wireless communications. Each control panel includes a computer processing unit with a nontransitory medium to store instructions, algorithms, and the like.

The thermostat 102 has a display 103, which can be a touch screen display, an onboard computer processing unit housed within its housing, and nontransitory memory, i.e., computer readable media, in which is stored a heating instruction, a cooling instruction, algorithms, and optionally, a priority instruction and a reversing instruction. The heating instruction is activated when the thermostat 102 receives a demand for space heating. The heating instruction causes the thermostat 102 to signal the first control panel 116 for operation of the hydronic air handler 106. More particularly, the thermostat 102 signals the first control panel 116 to activate the primary pump 112 to circulate water from the tankless hot water heater 104 to the hydronic air handler 106 and, when the tankless hot water heater senses water flow as a result of the primary pump's activation, the tankless hot water heater begins to heat water to meet the setpoint demand from the thermostat 102. When the heating setpoint demand is achieved, the thermostat 102 signals the first control panel 116 to deactivate the primary pump 112, which causes the tankless water heater 104 to sense an absence of water flow, thereby deactivating the tankless hot water heater.

When there is a demand for hot water for use within the building, the sensor 132 (priority switch) detects a drop in static pressure within the hot water supply piping. Depending upon how the system is configured, the sensor or priority switch 132 can send its measurement data or signal to either the thermostat 102 or the first control panel 116. Whichever receives the signal from the sensor 132 will have stored therein, in its nontransitory memory, a priority instruction. The priority instruction is, upon receipt of an indication of use of hot water in the building from the sensor or priority switch 132, to signal the third control panel 136 from the first control panel 116 to energize/activate the tankless hot water heater 102 and provide hot water to the plumbing fixtures, dishwashers, etc. that are in demand thereof and to deactivate or delay activation of the primary pump 112 for a preselected period of time.

The reversing instruction may be stored in the computer processing unit of the thermostat 102, the first control panel 116, or the second control panel 134. The reversing instruction is for operation of the heat pump in reverse to heat air in the spring and fall when exterior ambient temperatures are suitable, rather than activate the primary pump 112 and the tankless hot water heater 102. The reversing instruction, upon an indication from the temperature sensor of ambient air temperature being warmer than a predetermined set point temperature and a call for heat, activates the reversing valve of the heat pump to send heated refrigerant to the evaporator coil 108 to heat air passing over the evaporator coil and the first control panel keeps the primary pump off.

Referring now to FIGS. 3 and 4, the hydronic air handler 106 has a hydronic coil 202 positioned above a blower 204, which can be mounted at an angle relative to a chute outlet 207 of a chute 206 directing air flow from the blower 204 into direct contact with and through the hydronic coil 202 and out a primary outlet 209 of the hydronic air handler 106. The section of the housing 200 enclosing the blower 204 may include a sound attenuating material 210 positioned to reduce sound noise generated by the blower during operation of the unit, and optional knockout access panels 220 for connection to an air return duct. The blower 202 has a motor 212 operating a fan that directs air through the chute 206 toward the hydronic coil 202. The hydronic coil 202 has a hot water inlet 214 in fluid communication with the primary pump 112 (FIG. 1) and receives hot water from the tankless hot water heater 104 to warm air passing over the hydronic coil 202 and has a water outlet 216 in fluid communication with the tankless hot water heater 104 to send water back thereto to be heated again.

As best seen in FIG. 3, the hydronic air handler 106 has a terminal 222 which is a mounting surface for onboard terminals 244 and 226 and has a slot 223 for an optional interface card 225, which are all in electrical communication with the first control panel 116. The onboard terminal 224 is configured for plug-and-play electrical connections to the thermostat 102, the building's power source, the primary pump (power and communication), and a ground wire. The optional slot 223 for an interface card is for a card programmed to interface with any of the other units in the system, such as the tankless hot water heater, the sensor, or the heat pump. The terminal for the thermostat may be a 24V terminal 224 and the building's power may require 120V terminal 226. The housing 200 can include knockout access openings 228 for wires to reach the terminals 224, 226.

In the exploded view of FIG. 4, the housing 200 includes a bottom panel 230, a partition panel 232 separating the blower 204 from the hydronic coil 202, except for the chute outlet 207 defined thereby, and a top panel 234 defining the primary outlet 209 and having openings that receive the inlet and the outlet of the hydronic coil. Each of these panels 230, 232, and 234 are oriented horizontally (parallel to the ground). A front panel 238 is present and includes a handle 240 and an indicator 242. Additionally, a connection frame 244 for connection to the air return duct can be positioned against a selected knockout access panel.

The first control panel 116 or other computer processing unit 102, 136 in the system has a first instruction stored in its nontransitory memory to deactivate or delay activation of the primary pump 112 by a predetermined period of time when the thermostat 102 sends a call for heat to the first control panel 116 and the first control panel 116 has an indication of hot water flow to the hot water supply of the building. The indication of hot water flow to the building may come from sensor 132, the third control panel 136 of the tankless hot water heater 104, or the thermostat 102, any of which may directly indicate or have a computer processing unit that can be programmed to indicate hot water use within the building. The predetermined time period can be 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, or the typical number of minutes for the dishwasher, washing machine, etc. of the building, which ever has the longest cycle. In the system of FIG. 1, a demand call from the thermostat 102 signals the hydronic air handler 106, which turns on the primary pump 112 and then the blower 204. When the primary pump 112 turns on, a switch therein signals the tankless water heater 102 to heat the water. In this system, the primary pump 112 is not turned on in response to a call for heat when the sensor 132 senses hot water use, the third control panel 136 of the tankless hot water heater 104 indicates hot water use, or the thermostat 102 indicates hot water use within the building. Rather, after the predetermined period of time has passed, the first control panel 116 will signal the primary pump 112 to turn on and will instruct the tankless hot water heater to produce hot water. The primary pump 112 will be “on” at normal operating gallons per minute until the thermostat achieves a setpoint and the call for heat has been satisfied.

When the setpoint demand from thermostat 102 is achieved the first control panel 116 sends a signal to tankless hot water heater 104 to de-energize, and, in accordance with a first blower instruction, the blower motor 204 and the primary pump 112 will continue to operate for a set period of time determined by control panel 116 or the thermostat 102 to circulate water through hydronic coil 202. The first blower instruction is stored in the computer processing unit of either the thermostat 102 or the first control panel 116. This extended run time of the blower motor and primary pump scrubs off residual heat stored in the water piping between water heater 104 and air handler 106 and the hydronic coil 202 and the heat exchanger in the tankless hot water heater 104. This increases the overall efficiency of the space heating.

During the time when there is not a call for air-conditioning or heating, either from the heat pump 110 or the tankless hot water heater 104, the blower motor 204 in the air handler 106 can continue to operate at reduced cubic feet per minute (CFM) or part loads based on an additional instruction, a second blower instruction, stored in the nontransitory memory of the CPU of the first control panel 116 or the thermostat 102. This provides air flow throughout the building for a ventilation period of time, thereby meeting various ventilation requirements. In one embodiment, the ventilation period of time is twenty four hours, seven days a week. In other embodiments, the ventilation period of time less than twenty four hours at period times within a twenty four hour period.

The first control panel 116 can have a refresh instruction stored in the computer processing unit as well. The refresh instruction is configured to activate the primary pump 112 at preselected intervals within each 24 hour period to circulate water within the water piping and the hydronic coil 202 to prevent stagnation of water within the system. The preselected interval may be any number of hours within the range of 4 to 12 hours, thereby refreshing the system up to six times, 4 times, or 2 times in a 24 hour period.

Turning now to FIG. 5-7, the heat pump 110 is shown in more detail, which as noted with respect to FIG. 1 is exterior to the wall(s) 114 of the building. With reference to FIG. 5, the heat pump 110 has a housing 300 that includes a front grill 302, a top cover 304 and a valve cover 306. Protruding from the valve cover 306 are the supply conduit 308 and the return conduit 310. With reference to FIG. 6, the housing includes a front cabinet plate 312 defining a circular opening for the fan 314 to draw air across a condenser 320 (FIG. 7), right side plate 315, left side plate 317, base 319, and clapboard 313 separating the fan compartment form the compressor compartment. The fan 314 is operated by motor 315 (FIG. 7) that is held in place in the housing by the motor support sub-assembly 326. Seated below the top cover 304 is a first electrical box 316 and a second electrical box 318 housing various electronic components for the operation of the heat pump 110. A second control panel 134 (FIG. 1) is housed inside the second electrical box 318.

As shown in FIG. 7, the heat pump 110 has a condenser 320 filled with a refrigerant, a compressor 322 to operatively move the refrigerant through the system, an electric heater 323, and a reversing valve 324 in fluid communication with the compressor and the condenser to control the flow of the refrigerant from the condenser 320 to the evaporator coil 108 within the building. The condenser 320 is protected from damage from the exterior environment by a rear grill 328. The heat pump 110 also includes a valve support plate 330 supporting a two-way valve 332 on the liquid side of the heat pump and a three-way valve 334 on the gas/suction side of the heat pump. The heat pump 110 typically is used to provide air conditioning (cooling) in the summer months and spring and fall when temperatures require cooling of the space within the building and the thermostat 102 executes the cooling instruction and sends a demand for cooling to the first control panel 116 and/or the second control panel 134. The cooling instruction sends an activation signal to the second control panel 134 either directly or through the first control panel 116 to activate the heat pump in its normal mode, which sends cold refrigerant to the evaporator coil 108 within the building and sends an activation signal to the first control panel 116 to turn on the blower 204 of the hydronic air handler 106. When the cooling setpoint demand is achieved, the thermostat 102 signals the first control panel 116 or the second control panel 134 to deactivate the heat pump 110 and signals the first control panel 116 to subsequently (after a predetermined period of time) or simultaneously to deactivate the blower 204.

Returning to FIG. 1, the system of also includes a temperature sensor 150 for determining ambient air temperature at the exterior of the building. The temperature sensor 150 can be an actual sensor positioned at the exterior of the building proximate the heat pump or one built into the heat pump to sense the ambient air temperature at the exterior of the building. In another embodiment, the temperature sensor 150 is from a digital source connected to the thermostat over the internet or any other electronic communication format know or herein after developed, e.g., a local weather station, local weather web page, etc., i.e., it is not physically located proximate the heat pump or the building but still communications the ambient air temperature relative to the building.

The thermostat 102 is in operative communication with the second control panel 134 of the heat pump, either directly or through the first control panel 116 of the hydronic air handler 106. The thermostat 102 has a second instruction that utilizes the ambient air temperature from the temperature source 150 compared to a predetermined setpoint temperature to determine, when based on a call for heat, to leave the primary pump 112 off and to activate the reversing valve 324 of the heat pump 110 to send heated refrigerant to the evaporator coil 108 to heat air passing over the evaporator coil 108 using the blower 204 of the hydronic air handler 106. Since heat pumps lose efficiency during the colder months the thermostat 102 has an algorithm stored in its nontransitory memory that is executable by the onboard computer processing unit. The algorithm instructs the thermostat to only run heat pump in reverse during the “should seasons,” basically spring and fall, when the efficiencies are best for extracting heat from the ambient exterior air. When ambient exterior temperature falls below the predetermined setpoint, the system automatically switches to the on demand tankless hot water heater 102 to provide hot water to the hydronic coil 202 in the hydronic air handler 106 and activates the primary pump 112 as described above. Optionally, instead of an outdoor temperature sensor 150, the thermostat 102 may have a preprogrammed algorithm within the nontransitory memory which monitors cycle times and operation time of the heat pump to simulate outdoor air temperature and calculate the best time (balance point) to cycle between the heat pump for primary heat or the hydronic air handler as the primary heat source. Energy modeling shows a significant reduction in carbon emissions when using the heat pump during spring and fall heating cycles. This system may be referred to as “eco-friendly.”

Referring now to FIG. 9, in another aspect, we disclose a hydronic kit 460 for converting existing air handler-heat pump heating systems 400 for a building 114 with a hot water generating system 405, such as a hot water tank or tankless unit, to function as described above. The hydronic kit 460 has a hydronic coil 462, a primary pump 464, a control interface circuit 466, a wiring harness 468, and optionally, a sensor 469. The air handler is reference 407 and the heat pump is reference 410. The primary pump 464 is configured to be connected in fluid communication with the hydronic coil 462 and in fluid communication with hot water from a hot water generating system 405. The primary pump 464 is configured to pump hot water into the hydronic coil 462 when warm air is demanded by a thermoset 402. The control interface circuit 466 has a computer processing unit 467 with nontransitory memory connectable to a control panel 416 of an air handler-heat pump system 400 and is configured to control activation of a blower (not shown) within the air handler 407 of system 400. The sensor 469 is positionable downstream of a cold-hot water mixing valve 428 to determine flow of hot water in the hot water supply of the building and is configured for operative communication with the control interface circuit 466 and/or the control panel 416 of the air handler-heat pump system 400. The wiring harness 468 is configured to connect the primary pump 464 and the hot water generating system 405 to the control panel 416 of the air handler-heat pump system 400. The control interface circuit 466 stores a priority instruction that upon an indication from the sensor 469 of hot water flow in the hot water supply of the building, a deactivation or delay activation signal is sent to the primary pump 464 to deactivate or delay activation for a predetermined period of time as described above.

In FIG. 9, normal operation, without the hydronic kit 460 option, the thermostat 402 sends a signal to the control panel 416 in the air handler 407 that the setpoint demand has been achieved, the control panel 416 then deenergizes the blower of the air handler 407 and deenergize the supplemental heating element 409 in the air handler 407 if it is in operation. Since there are many brands of air handler-heat pump systems on the market it would be difficult to design a control interface circuit 466 for each control panel 416 for the various brands. It is preferable to use the control signal from the thermostat 402 as the mechanism to activate the pump 464 in the hydronic kit 460, to interface with the control panel 416 to control the blower of the air handler 407, and to activate/deactivate the supplemental heating element 409 in the various air handlers available.

In operation, when the hydronic kit is installed instead of the supplemental heating element 409 in the air handler 407, the signal from the thermostat 402 that would normally be connected directly to the air handler 407 by low voltage wiring is interrupted by the control interface circuit 466. The computer processing unit 467 of the control interface circuit 466 is configured to modify the signal from the thermostat 402. During a call for heat from the thermostat 402, the thermostat 402 sends a signal to the control panel 416, the signal is then modified by the computer processing unit 467 of the control interface circuit 466 and the modified signal activates the primary pump 464. For example, a 110V/24V relay within the control interface circuit 466 activates the 110V pump 464. The control interface circuit 466 then completes the electrical circuit, thereby allowing the signal from the thermostat 402 to activate the blower thru control panel 416 of the air handler 407. The control panel 416 will then operate the air handler 407 and heat pump 410 as normally programmed from the factory whether in heating or cooling mode as dictated by the thermostat 402. The evaporator coil 408 will still provide heat from the heat pump 410 in addition to the heat provided by the hydronic kit 460 reaching the desired setpoint demand from the thermostat 402 in the same configuration as if the electric heating element had been used. The computer processing unit 467 in the control interface circuit 466 can be programmed with the same instructions described above for the embodiment of FIG. 1, except for the blower control which is controlled by the air handler's control panel 416.

One of the instructions, is a reversing instruction that, upon an indication from the temperature sensor 450 of ambient air temperature being warmer than a predetermined set point temperature and there being a call for heat, activates a reversing valve 435 of the heat pump 410, a factory component therein, to send heated refrigerant to the evaporator coil 408 to heat air passing over the evaporator coil and signals the control interface circuit 466 to keep the primary pump 464 deactivated.

In one embodiment, the control interface circuit 466 is configured for switching between hydronic heating-heat pump mode and air handler-heat pump mode. In one embodiment, a mode selector dip switch is present to selected either the hydronic heating-heat pump mode or the air handler-heat pump mode. The air handler-heat pump mode will use an electric heating element to supplement the heat pump when the heat pump cannot meet the heat demand in its standard factory mode of heating/air conditioning, which will be less efficient than the hydronic heating-heat pump mode for heating the building.

Still referring to FIG. 9, the hydronic kit 460 can include a temperature sensor 450 configured for operative communication with the control interface circuit 466. The temperature sensor 450 can be mountable at a position exterior to the building 114 to sense ambient air temperature generally proximate the heat pump 410. In another embodiment, the temperature sensor 450 is a digital source in electrical communication with the control circuit interface 466. Possible examples of the digital source are provided above with respect to the discussion of FIG. 1. Optionally, instead of an outdoor temperature sensor 450, the thermostat 402 may have a preprogrammed algorithm within the nontransitory memory, which monitors cycle times and operation time of the heat pump to simulate outdoor air temperature and calculate the best time (balance point) to cycle between the heat pump for primary heat or the hydronic air handler as the primary heat source.

Besides more efficient, economical heating using the hydronic kit, the building owner may be able to benefit from gas and electric utility rebates for installing a unit that reduces the carbon footprint. In some jurisdictions, there may be a rebate from the electric utility for the installation of an air handler-heat pump system. When this system is modified by the installation of the hydronic kit, the owner of the building may qualify for a rebate from the gas utility as well.

In British Columbia, Canada, the Energy Step Code measures a building's energy performance by a variety of metrics. The Building Envelope Metrics and the Equipment and Systems Metrics are demonstrated through a whole-building performance simulation. For the Building Envelope Metrics, thermal energy demand intensity is the amount of annual heating energy needed to maintain a stable interior temperature, taking into account heat loss through the envelope and passive gains (i.e., the amount of heat gained from solar energy passing through the envelope, or from activities in the home such as cooking and lighting, and that provided by body heat). It is calculated per unit of area of the conditioned space over the course of a year and expressed in kWh/(m²·year). For Equipment and Systems Metrics, the first metric is “Percent Lower than EnerGuide Reference House.” This establishes how much energy a home would use if it was built to base building code standards. This metric identifies how much less energy, stated as a percentage, the new home will require compared to the reference house. The second metric is “Mechanical Energy Use Intensity.” This metric models the amount of energy used by space heating and cooling, ventilation, and domestic hot water systems, per unit of area, over the course of a year, expressed in kWh/(m²·year). The third metric is “Total Energy Use Intensity.” This third metric models the amount of total energy use by a building per unit area, over the course of a year, expressed in kWh/(m²·year).

The hybrid systems disclosed herein, with the hydronic air handler, meet the second metric of the Mechanical Energy Use Intensity. This is said to achieve an Energy Step Code rating of 4 out of 5, which is a high rating exceeding existing space heating and cooling units. The hydronic air handler, a high efficiency tankless hot water heating unit to heat hot water, and a heat pup operating in the shoulder season collectively use less energy per unit area.

Although the invention is shown and described with respect to certain embodiments, it is obvious that modifications will occur to those skilled in the art upon reading and understanding the specification, and the present invention includes all such modifications.

Claims

1. An air heating and potable water system of a building comprising: a thermostat having a computer processing unit with nontransitory memory comprising a heating instruction;a hot water heater having a water heater control panel having a computer processing unit;a hydronic air handler having a hydronic coil, a blower, and a first control panel having a computer processing unit with nontransitory memory, wherein the first control panel is in operative communication with the thermostat, and the hydronic coil is in fluid communication with the hot water heater and receives hot water from the hot water heater to warm air passing over the hydronic coil;a primary pump controlling the fluid communication of the hot water from the hot water heater into the hydronic coil, the primary pump being in operative communication with the first control panel; anda indicator of hot water supply usage within the building and in operative communication with either the thermostat or the first control panel;wherein either the computer processing unit of the thermostat, the first control panel, or the water heater control panel stores a priority instruction;wherein, the priority instruction upon an indication of hot water flow to the hot water supply of the building directly from the sensor deactivates or delays activation of the primary pump by a predetermined period of time.

2. The system of claim 1, wherein the priority instruction is configured to send a signal to the hot water heater to activate the hot water heater, which provides hot water to the hot water supply of the building while the primary pump is deactivated or delayed for the predetermined period of time.

3. The system of claim 1, wherein the hot water heater is a tankless gas or electric hot water heater, a hydrogen eater splitting hot water heater, or a Peltier thermoelectric hot water heater.

4. The system of claim 1, wherein the thermostat is in direct electrical communication or has a wireless communication with the control panel of the hydronic air handler and the sensor.

5. The system of claim 1, wherein the primary pump is external to the hydronic air handler.

6. The system of claim 1, wherein the indicator of hot water supply usage within the building is a pressure sensor or a fluid flow sensor compatible with potable water positioned in the hot water supply of the building, is the hot water heater control panel, or the thermostat.

7. The system of claim 1, wherein the predetermined period of time is selected from the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30 minutes.

8. The system of claim 1, wherein the predetermined period of time is equivalent to the minutes for a cycle of an appliance within the building that uses hot water.

9. The system of claim 1, wherein, the first control panel or the thermostat stores a first blower instruction in the computer processing unit thereof to continue activation of the blower and primary pump for a post-heat period of time; wherein, after a setpoint demand for heat has been reached, the blower instruction signals the blower and the primary pump to continue activation thereof for the post-heat period of time to utilize residual heat stored in any of the components in the system.

10. The system of claim 9, wherein the first control panel or the thermostat stores a second blower instruction in the computer processing unit thereof to run the blower at a reduced rate when there is no call for air-conditioning or heating for a ventilation period of time.

11. The system of claim 1, comprising: a heat pump positioned exterior to the building, the heat pump comprising a condenser, a refrigerant within the condenser, a compressor, a second control panel having a computer processing unit with nontransitory memory, and a reversing valve;an indicator of outdoor ambient air temperature;an evaporator coil within the interior of the building is in fluid communication with the condenser of the heat pump and the evaporator coil is in fluid communication with the blower of the hydronic air handler for passing air over the evaporator coil;wherein the thermostat is in operative communication with the second control panel and has a cooling instruction for activating the heat pump to provide air conditioning to the building;wherein either the computer processing unit of the thermostat, the first control panel, or the second control panel stores a reversing instruction;wherein, the reversing instruction, upon an indication of outdoor ambient air temperature being warmer than a predetermined set point temperature and a call for heat, activates the reversing valve of the heat pump to send heated refrigerant to the evaporator coil to heat air passing over the evaporator coil and the first control panel keeps the primary pump deactivated.

12. The system of claim 11, wherein the indicator of ambient air temperature is a temperature sensor at the exterior of the building in operative communication with the thermostat or is a temperature algorithm stored in nontransitory memory of the thermostat that is configured to monitor cycle times and operation times of the heat pump to simulate outdoor air temperature and calculate when the heat pump or the hydronic air handler acts as primary heat source.

13. The system of claim 11, wherein the temperature sensor is a sensor positioned to sense ambient air temperature at the exterior of the building or is a digital source in electrical communication to the thermostat.

14. A hydronic kit for an air handler-heat pump system in a building with a hot water generating system comprising: a hydronic coil;a primary pump configured to be connected in fluid communication with the hydronic coil to pump hot water into the hydronic coil and in fluid communication with hot water from a hot water generating system;a control interface circuit having a computer processing unit with nontransitory memory connectable to a control panel of an air handler-heat pump system and configured to control activation of a blower of the air handler-heat pump system and configured to receive an indication of hot water supply usage within the building;a wiring harness configured to connect the primary pump and the hot water generating system to the control panel of the air handler-heat pump system;wherein the control interface circuit stores a priority instruction that upon receipt of an indication of hot water supply usage within the building, a deactivation or delay activation signal is sent to the primary pump to deactivate or delay activation for a predetermined period of time.

15. The hydronic kit of claim 14, wherein the deactivation or delay activation signal is sent from a thermostat in the building to the primary pump.

16. The hydronic kit of claim 15, further comprising a sensor positionable to determine flow of hot water in a hot water supply of a building and configured for operative communication with the control interface circuit, the thermostat, and/or the control panel of the air handler-heat pump system.

17. The hydronic kit of claim 16, wherein the sensor is a pressure sensor or a fluid flow sensor and is compatible with potable water.

18. The hydronic kit of claim 14, wherein the predetermined period of time is selected from the group consisting of 15 minutes, 20 minutes, 25, minutes, and 30 minutes.

19. The hydronic kit of claim 14, wherein the control interface circuit is configured for switching between hydronic heating-heat pump mode and air handler-heat pump mode.

20. The hydronic kit of claim 15, further comprising: an indicator of outdoor ambient air temperature;wherein the control interface circuit stores a reversing instruction, which, upon an indication of outdoor ambient air temperature being warmer than a predetermined set point temperature and a call for heat, is configured to activate a reversing valve of the heat pump to send heated refrigerant to the evaporator coil to heat air passing over the evaporator coil while the control interface circuit keeps the primary pump deactivated.

21. The system of claim 20, wherein the indicator of ambient air temperature is a temperature sensor at the exterior of the building in operative communication with the thermostat, is a digital source in electrical communication with the thermostat or the control circuit interface, or is a temperature algorithm stored in nontransitory memory of the thermostat that is configured to monitor cycle times and operation times of the heat pump to simulate outdoor air temperature and calculate when the heat pump or the hydronic air handler acts as primary heat source.