CONTROLLER AND METHOD FOR MULTI-ZONE AIR HEATING AND COOLING SYSTEM WITH MOTORIZED VENTS

Abstract

A method of controlling a zoned, building air heating, cooling or air conditioning system to control the temperature environment of the individual zones without the use of on-demand heating and cooling sources that consume energy includes collecting data from a plurality of zone temperature sensors; monitoring the temperature sensor data in substantially real-time; generating a trigger signal when zone temperature sensor data is different from predefined zone temperature sensor threshold values; ranking the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value; and adjusting the opening and closing of a plurality of motorized air ventilation ports in the zones according to the rankings of the zones, and activating a fan that moves air between the zones that have open ventilation ports, when the trigger signal is present.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

n/a

TECHNICAL FIELD

This invention relates generally to heating, ventilation, and air conditioning (HVAC) systems and more particularly to computer and remote control of motorized air vents and air heating and cooling sources.

BACKGROUND

In residential HVAC systems, and particularly in smaller homes, it is common to install the entire HVAC system as one zone with one control thermostat for installation cost savings and ease of installation. It is however difficult to maintain a desired temperature environment in all rooms in such systems.

If it is desired to maintain the same temperature environment in all rooms, the resident may manually adjust individual room air vents in an attempt to balance the amount of heat or cooling provided from the heated or cooled air coming from the heating or cooling source. However, depending on the time of day, the amount sunlight coming in, the temperature outside, and other factors, this balancing may be reasonably effective in some circumstances and entirely ineffective at other times. If it is desired to maintain different temperatures in individual rooms, this imbalance problem is exacerbated further because the thermostat control exists only in one location, perhaps not even near a vent. For these reasons some rooms become overheated, some under-heated, and this situation changes in a generally uncontrollable manner.

It is therefore desirable to provide zoning to HVAC systems such that each designated zone has individual control over the local temperature. If provided, such zoned systems are normally installed in the initial system by placing motorized dampers in the ducts leading to the vents, the dampers being under the control of multiple thermostats. In such systems, any thermostat may call for heating and/or cooling at any time. However, retrofitting an existing single-zone system to become a multi-zone system can be problematic because of the need to runs wires, retrofit dampers in the walls or ceilings of ductwork; further, retrofitting even if feasible, can be expensive.

It is therefore desirable to provide a means of inexpensively retrofitting a single-zone system to create a multi-zone system without running wires or installing intra-duct dampers. Several systems exist that provide some degree of functionality aimed at such retrofits for individual zoning of HVAC systems. One such system provides closing of vents in rooms that are being overheated in the winter and/or overcooled in the summer according to the temperature in the room as measured by a temperature measuring device in the room. However this system still relies on the same, originally installed single thermostat to create a heating or cooling call and therefore cannot arbitrarily heat a cold room or cool a hot room. It is therefore desirable to provide zoning to HVAC systems such that each designated zone has individual control over the local temperature by: a) closing vents in rooms that are being overheated in the winter and/or overcooled in the summer, and b) by causing the heating or cooling system to turn on according to the temperature in any individual room zone independent of a “central” thermostat. It is desirable to create a multi-zone heating and cooling system that can be retrofitted to a single zone system wherein any zone can call for heating or cooling and can also limit the heating and cooling of a particular zone when other zones require the system to be on.

In HVAC systems, a fan is used to provide distribution of the heating or cooling through the air vents. If many vents are partially or completely closed, the running of the fan may cause an undesirable back pressure when operating. This results in hot or cool air leakage into uncontrolled spaces in walls and between floors, and can also cause “whistling” noise from partially closed vents because of increased air flow velocity. For this reason, existing retrofit multi-zone systems with motorized vents will sometimes recommend that not every vent in the system be automated so that the back pressure is never so great as to cause a problem. This restriction partially defeats the primary reason for having the multi-zone system in the first place, because not every vent is controlled. It is therefore desirable to create a multi-zone heating and cooling system wherein the undesirable air leakage and noise is prevented by controlling against too much backpressure through controlling the number of vents that are completely closed and/or controlling the fan speed.

In HVAC systems, when a zone is too cold during the heating season, or too hot during the cooling season, the fan is turned on and a heating or cooling source is also activated. These heating and cooling sources are the main users of energy in such systems. However, at times in the heating season, for example, there are rooms that are too cold and simultaneously there are rooms that are warmer than their thermostat setpoints. In such a case, in order to save energy, it would be desirable to have intelligent control of the vents and the fan such that the system could, by selective opening and closing of vents and turning on of the fan, move warm air from some of the warmer rooms to some of the colder rooms, without turning on the heating source. Similarly, in cooling season, the system could move cool air from some of the cooler rooms to some of the warmer rooms by controlling vents and the fan, without turning on the cooling source.

In large buildings and commercial installations, it is not uncommon to have some rooms that are too hot almost all of the time, and other rooms that are too cool almost all of the time. In such situations, control schemes for a multi-zone HVAC system similar to that described above could be used to lower energy costs by using waste heat from the warm rooms to warm the cold rooms, or vice versa, to use waste cooling from the cool rooms to lower the temperature in too-warm rooms, all without causing the heating or cooling source to operate.

SUMMARY

The present invention advantageously provides for a building air heating, cooling and air conditioning (HVAC) system including a plurality of temperature-controlled zones, each zone with at least one motorized air ventilation port. At least one of a heating source and a cooling source is included, the at least one of the heating source and the cooling source includes a fan fluidly connected to the ventilation ports with air ducts. A plurality of zone temperature sensors source positioned to measure the air temperatures in the plurality of temperature-controlled zones are included. At least one return-air port is fluidly coupled to at least one of the heating source and the cooling source. A controller is in communication with the plurality of motorized air ventilation ports, the plurality of zone temperature sensors, and the at least one of the heating source and the cooling source, the controller includes a sensor interface configured to communicate with the plurality of temperature-controlled zones; a plurality of sensors configured to receive zone temperature sensor data; a monitoring module configured to monitor the zone temperature sensor data in substantially real-time; a trigger module configured to generate a trigger signal when the zone temperature sensor data is different from a predefined zone temperature sensor threshold value; a ranking module configured to rank the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value; an actuator module configured to communicate with the trigger module and the ranking module and configured to generate control signals to adjust the opening and closing of the plurality of air ventilation ports according to the rankings of the temperature-controlled zones and activate the at least one of the heating source and the cooling source and the fan.

In yet another embodiment, the controller of the HVAC system that communicates with a plurality of motorized air ventilation ports, a plurality of zone temperature sensors, and an on-demand heating or cooling source including a fan includes a sensor interface configured to communicate with the plurality of zone temperature sensors to receive zone temperature sensor data; a monitoring module configured to monitor zone temperature sensor data in substantially real-time; a trigger module configured to generator a trigger signal when the zone temperature sensor data is different from predefined zone temperature sensor threshold value; a ranking module configured to rank the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value; an actuator module configured to communicate with the trigger module and the ranking module and generates control signals to adjust the opening and closing of the plurality of air ventilation ports according to the rankings of the temperature-controlled zones and activate the at least one of the heating source and the cooling source and the fan.

In yet another embodiment, a method of controlling a zoned, building air heating, cooling or air conditioning system to control the temperature environment of the individual zones without the use of on-demand heating and cooling sources that consume energy includes collecting data from a plurality of zone temperature sensors; monitoring the temperature sensor data in substantially real-time; generating a trigger signal when zone temperature sensor data is different from predefined zone temperature sensor threshold values; ranking the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value; and adjusting the opening and closing of a plurality of motorized air ventilation ports in the zones according to the rankings of the zones, and activating a fan that moves air between the zones that have open ventilation ports, when the trigger signal is present.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

FIG. 1 illustrates wireless and wired communications components of an exemplary heating and cooling system according to one embodiment of the invention;

FIG. 2 illustrates the air ducting connections and open/closed conditions of the vents for one particular heating situation for an exemplary system according to one embodiment of the invention;

FIG. 3 illustrates a flow chart for controlling opening and closing of vents and operation of the heating and cooling sources for the system controller according to one embodiment of the invention; and

FIG. 4 illustrates the air ducting connections and open/closed conditions of the vents for a particular cooling situation for an exemplary system incorporating outside air intake according to one embodiment of the invention.

DETAILED DESCRIPTION

FIG. 1 illustrates the communications channels of a typical configuration for an air heating or cooling system according to one embodiment of the invention. Items 10 through 1N are motorized air diffusion vents in temperature controlled zones, those zones being monitored and controlled in part by wireless thermostats, 21 through 2N. Each thermostat is in wireless communications, 51 through 5N with the vent for that zone. In this example, each zone has only one vent, but in many systems there may be more than one vent in a zone. In that case, the thermostat for each such zone communicates with all the vents in that zone. The thermostats are also in wireless communication with the system central controller 31. Although the communications set forth in this example are wireless, any of the wireless communications channels could be replaced by a wired communications channel without altering the fundamental functioning of the communications.

System central controller 31 is in wired communication 32 with the heating or cooling source 41, which itself includes a fan 42. In a preferred embodiment, the fan may be separately controlled from the heating or cooling function. For example, an air furnace may have input connections for turning on and off the fan to create air movement, and separate input connections for turning on and off the burner to produce heat.

FIG. 2 illustrates the duct work for directing the air movement in an exemplary system with three zones. The illustration presents the system at a particular time when there is heat being delivered to two zones through motorized vents 10 and 11 from the heat source 41 via ductwork 101. Motorized vent 12 is closed because that zone does not need heat. According to one embodiment of the invention, the central controller includes a computer which collects temperature and thermostat data from the zone thermostats, and ranks them according to how far from the thermostat setpoint (“temperature sensor threshold value” in the claims) the temperature in the room actually is. For example, the thermostat for the zone covered by vent 10 may be set to 70 degrees and the zone temperature is 65 degrees. The difference for that zone, for purposes of ranking is 5 degrees and the zone is presenting a “call for heat.” At the same time, the difference for the zone covered by vent 11 may be, for example, 2 degrees, presenting another call for heat, and the difference for the zone covered by vent 12 may be −3 (the zone is warmer than the thermostat setpoint) and the zone is not presenting a call for heat. The central controller 31 is programmed to therefore rank the zones and open the motorized vents such that vent 10 is open more than vent 11 according to the ranking, and to leave vent 12 closed, also according to the ranking, and to turn on the heat source 41 and fan 42. Thereby, more heat is delivered to the zone covered by vent 10 than to the zone covered by vent 11 and no heat is delivered to the zone covered by vent 12. This ranking and partial opening of vents according to ranking will have the consequence of decreasing the furnace runtime because heat is being delivered in accordance with a zone's need for it, as determined by the ranking. The controller is further programmed to repeat the data collection and ranking cycle on a regular time interval as heat is being delivered, in order to adjust the vent openings dynamically as the zones warm up. The goal is to have each of the zones presenting a call for heat reach its thermostat setpoint at approximately the same time.

FIG. 2 in combination with FIG. 3 can also be used to illustrate another capability of the invention. Consider a particular time when the zone covered by vent 10 has a significant negative ranking (e.g., −10, meaning the zone is 10 degrees hotter than the thermostat setpoint). This could be, for example, due to sunlight entering the room in the late afternoon and warming the zone considerably. At the same time, there may be another zone, say the zone covered by vent 11, which is below its thermostat setting and thus may have a ranking of 5 and be presenting a call for heat. According to one embodiment of the invention, the central controller 31 is programmed to recognize a situation wherein at least one zone has a significant negative ranking and at least one zone has a positive ranking. In this scenario, the controller is further programmed to adjust the motorized vents such that vent 10 and vent 11 are both opened fully, while vent 12 is kept closed, and to turn on only the fan 42, keeping the heating function of the heat source 41 turned off. By doing this, the return air streams from the two zones with open vents (10 and 11) are mixed in the return air vent 9 and the return air ducts 102, and redistributed back to the same two zones. The overall result is the bringing of the two zones towards some intermediary temperature; in other words, the excess heat from the zone of vent 10 is used to warm the zone of vent 11, without use of electric or other fuel for heating air. Only the electric energy of the fan is utilized.

While the example just given is a demonstration of using excess heat of one zone to warm another zone, to those skilled in the art, it is obvious that a similar function can be achieved when desiring to cool one zone by using the coolness of another zone and mixing the return air streams of the two zones with only the system fan 42.

FIG. 4 illustrates another preferred embodiment of the invention which results in further energy savings for cooling applications. Consider a particular time when the zone covered by vent 10 in a building is warmer than the thermostat setpoint and would normally require the cooling source and fan to be on and vent 10 to be open. In this embodiment there are two return-air vents, 9 and 105. Return-air vent 9 allows air from inside the building to return to the cooling source and fan 41 and 42 via ducts 102. Return-air vent 105 allows air from outside the building to be delivered to the cooling source and fan 41 and 42 via ducts 102. In this embodiment, the central controller 31 is programmed to compare the temperature of the outside air as measured by a remote temperature measuring device (not shown) to the thermostat setpoint of the zone requesting cooling from the system. If the outside temperature is cooler than the thermostat setpoint, the controller closes return-air vent 9 and opens return-air vent 105, opens the vent 10, and turns on the fan 42, so that outside air is delivered to the zone covered by vent 10. This configuration is cooling the room without turning on the cooling source function and thus saves considerable energy. Vents 11 and 12 are kept closed because those zones need no cooling. Depending on the temperatures inside and outside the building and in particular in the zones requesting cooling, the controller may be further programmed to mix inside and outside air by opening each of vents 9 and 105 partially, to a chosen ratio.

It will be appreciated by persons skilled in the art that the disclosure is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings, which is limited only by the following claims.

It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope and spirit of the invention, which is limited only by the following claims.

Claims

1. A building air heating, cooling and air conditioning (HVAC) system, comprising: a plurality of temperature-controlled zones, each zone with at least one motorized air ventilation port;at least one of a heating source and a cooling source, the at least one of the heating source and the cooling source including a fan fluidly connected to the ventilation ports with air ducts;a plurality of zone temperature sensors source positioned to measure the air temperatures in the plurality of temperature-controlled zones;at least one return-air port fluidly coupled to at least one of the heating source and the cooling source;a controller in communication with the plurality of motorized air ventilation ports, the plurality of zone temperature sensors, and the at least one of the heating source and the cooling source, the controller including: a sensor interface configured to communicate with the plurality of temperature-controlled zones;a plurality of sensors configured to receive zone temperature sensor data;a monitoring module configured to monitor the zone temperature sensor data in substantially real-time;a trigger module configured to generate a trigger signal when the zone temperature sensor data is different from a predefined zone temperature sensor threshold value;a ranking module configured to rank the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value;an actuator module configured to communicate with the trigger module and the ranking module and configured to generate control signals to:adjust the opening and closing of the plurality of air ventilation ports according to the rankings of the temperature-controlled zones; andactivate the at least one of the heating source and the cooling source and the fan.

2. The system of claim 1, wherein the fan of the at least one of the heating source and the cooling source is activated by a control signal from the controller independently from activating the respective heating and cooling function of the at least one of the heating source and the cooling source.

3. The system of claim 1, where the controller is in wireless communication the plurality of motorized air ventilation ports, the plurality of zone temperature sensors, and the at least one of the heating source and the cooling source.

4. The system of claim 1, wherein the at least one return-air vent fluidly couples outside air to the fan the at least one of the heating source and the cooling source.

5. The system of claim 1, wherein the motorized ventilation ports are adjusted by the controller to be at least one of closed, fully opened, and partially opened.

6. The system of claim 1, wherein at least one of the return-air ports is motorized and controlled by the controller to be at least one of open, closed, and partially open.

7. A controller for controlling a building air heating, cooling and air conditioning (HVAC) system, that communicates with a plurality of motorized air ventilation ports, a plurality of zone temperature sensors, and an on-demand heating or cooling source including a fan, the controller comprising: a sensor interface configured to communicate with the plurality of zone temperature sensors to receive zone temperature sensor data;a monitoring module configured to monitor zone temperature sensor data in substantially real-time;a trigger module configured to generator a trigger signal when the zone temperature sensor data is different from predefined zone temperature sensor threshold value;a ranking module configured to rank the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value;an actuator module configured to communicate with the trigger module and the ranking module and generates control signals to:adjust the opening and closing of the plurality of air ventilation ports according to the rankings of the temperature-controlled zones; andactivate the at least one of the heating source and the cooling source and the fan.

8. The controller of claim 7, wherein the fan of the at least one of the heating source and the cooling source is activated by a control signal from the controller independently from activating the respective heating and cooling function of the at least one of the heating source and the cooling source.

9. The controller of claim 7, where the controller is in wireless communication the plurality of motorized air ventilation ports, the plurality of zone temperature sensors, and the at least one of the heating source and the cooling source.

10. The controller of claim 7, wherein the at least one return-air vent is fluidly couple outside air to the fan of the at least one of the heating source and the cooling source.

11. The controller of claim 7, wherein the motorized ventilation ports are adjusted by the controller to be at least one of closed, fully opened, and partially opened.

12. The controller of claim 7, wherein at least one of the return-air ports is motorized and controlled by the controller to be at least one of open, closed, and partially open.

13. A method of controlling a zoned, building air heating, cooling or air conditioning system to control the temperature environment of the individual zones without the use of on-demand heating and cooling sources that consume energy, the method comprising: collecting data from a plurality of zone temperature sensors;monitoring the temperature sensor data in substantially real-time;generating a trigger signal when zone temperature sensor data is different from predefined zone temperature sensor threshold values;ranking the plurality of temperature-controlled zones based at least on the difference between the real-time zone temperature and the predefined zone temperature sensor threshold value;adjusting the opening and closing of a plurality of motorized air ventilation ports in the zones according to the rankings of the zones, and activating a fan that moves air between the zones that have open ventilation ports, when the trigger signal is present.