Remote control of an HVAC system that uses a common temperature setpoint for both heat and cool modes
An HVAC system includes an HVAC unit having a cooling mode and a heating mode for conditioning the air in an inside space, and a programmable thermostat located remotely from the HVAC unit. The HVAC unit may have an onboard controller configured to control when the HVAC unit is in the cooling mode or heating mode, and whether the HVAC unit is activated or not. In some cases, the onboard controller of the HVAC unit may use a common temperature setpoint when controlling in the cooling mode and the heating mode. The programmable thermostat may have a programmable schedule with a plurality of time periods, where each time period has a heating setpoint and a cooling setpoint separated by a dead band. The onboard controller of the HVAC unit may be configured to accept input signals from the remotely located thermostat. The remotely located thermostat may send one or more input signals to the onboard controller of the HVAC unit in accordance with the programmable schedule, where the one or more input signals cause the onboard controller of the HVAC unit to set the HVAC unit to a particular one of the cooling mode and the heating mode, and to activate the HVAC unit so as to condition the air in the inside space in the particular one of the cooling mode and the heating mode.
1. A wireless thermostat for use with a mini-split HVAC unit, the mini-split HVAC unit including an onboard temperature sensor for sensing a temperature local to the mini-split HVAC unit and an onboard thermostatic controller operatively coupled to the onboard temperature sensor, the onboard thermostatic controller configured to store an onboard temperature setpoint and to thermostatically control the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the onboard temperature setpoint, the mini-split HVAC unit further including a wireless receiver for receiving an updated onboard temperature setpoint, the wireless thermostat comprising:
a wireless transmitter;
a thermostat temperature sensor configured to sense an air temperature local to the wireless thermostat;
a controller operatively coupled to the wireless transmitter and the thermostat temperature sensor, wherein the controller is configured to:
determine an updated onboard temperature setpoint based at least in part on a comparison between the air temperature sensed by the thermostat temperature sensor and a thermostat temperature setpoint; and
transmit the updated onboard temperature setpoint via the wireless transmitter to the wireless receiver of the mini-split HVAC unit so that the onboard thermostatic controller of the mini-split HVAC unit subsequently thermostatically controls the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the updated onboard temperature setpoint.
2. The wireless thermostat of claim 1 , wherein the updated onboard temperature setpoint is different from the thermostat temperature setpoint.
3. The wireless thermostat of claim 1 , wherein the controller of the wireless thermostat is configured to not transmit the updated onboard temperature setpoint to the wireless receiver of the mini-split HVAC unit when the comparison reveals a difference between the air temperature sensed by the thermostat temperature sensor and the thermostat temperature setpoint is less than a predetermined amount.
4. The wireless thermostat of claim 1 , wherein the wireless transmitter is an Infrared (IR) transmitter, and the wireless receiver is an IR receiver.
5. The wireless thermostat of claim 1 , further comprising a memory for storing the thermostat temperature setpoint, wherein the memory is operatively coupled to the controller.
6. The wireless thermostat of claim 5 , wherein the memory stores a programmable schedule with a plurality of time periods, where each time period has a corresponding the thermostat temperature setpoint, and during each of the plurality of time periods, the controller is configured to use the corresponding thermostat temperature setpoint when determining the updated onboard temperature setpoint.
7. The wireless thermostat of claim 1 , further comprising a user interface configured to allow a user to modify one or more operational parameters of the wireless thermostat including the thermostat temperature setpoint.
8. The wireless thermostat of claim 1 , wherein the mini-split HVAC unit comprises both a heating mode and a cooling mode, and wherein the wireless thermostat is configured to transmit a heating mode command via the wireless transmitter to the wireless receiver of the mini-split HVAC unit to set the mini-split HVAC unit to the heating mode.
9. The wireless thermostat of claim 8 , wherein the wireless thermostat is configured to selectively transmit a cooling mode command via the wireless transmitter to the wireless receiver of the mini-split HVAC unit to set the mini-split HVAC unit to the cooling mode.
10. A wireless thermostat for use with a mini-split HVAC unit, the mini-split HVAC unit including an onboard temperature sensor for sensing a temperature local to the mini-split HVAC unit and an onboard thermostatic controller operatively coupled to the onboard temperature sensor, the onboard thermostatic controller configured to store an onboard temperature setpoint and to thermostatically control the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the onboard temperature setpoint, the mini-split HVAC unit further including an wireless receiver for receiving an updated onboard temperature setpoint, the wireless thermostat comprising a housing for housing:
a user interface accessible by a user from outside of the housing for accepting a thermostat temperature setpoint from the user;
a transmitter;
a thermostat temperature sensor configured to sense an air temperature local to the wireless thermostat;
a controller operatively coupled to the user interface, the transmitter and the thermostat temperature sensor, wherein the controller is configured to:
determine an updated onboard temperature setpoint based at least in part on a comparison between the air temperature sensed by the thermostat temperature sensor and the thermostat temperature setpoint set by the user using the user interface; and
transmit the updated onboard temperature setpoint via the transmitter to the wireless receiver of the mini-split HVAC unit so that the onboard thermostatic controller of the mini-split HVAC unit subsequently thermostatically controls the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the updated onboard temperature setpoint.
11. The wireless thermostat of claim 10 , wherein the updated onboard temperature setpoint is different from the thermostat temperature setpoint accepted from the user via the user interface.
12. The wireless thermostat of claim 10 , wherein the controller of the wireless thermostat is configured to not transmit the updated onboard temperature setpoint to the wireless receiver of the mini-split HVAC unit when the comparison reveals a difference between the air temperature sensed by the thermostat temperature sensor and the thermostat temperature setpoint is less than a predetermined amount.
13. The wireless thermostat of claim 10 , wherein the transmitter is an Infrared (IR) transmitter, and the wireless receiver is an IR receiver.
14. The wireless thermostat of claim 10 , further comprising a memory for storing the thermostat temperature setpoint, wherein the memory is operatively coupled to the controller.
15. The wireless thermostat of claim 14 , wherein the memory stores a programmable schedule with a plurality of time periods, where each time period has a corresponding the thermostat temperature setpoint, and during each of the plurality of time periods, the controller is configured to use the corresponding thermostat temperature setpoint when determining the updated onboard temperature setpoint, and wherein the user interface is configured to accept from a user a start time for each of the plurality of time periods and a thermostat temperature setpoint for each of the plurality of time periods.
16. The wireless thermostat of claim 10 , wherein the mini-split HVAC unit comprises both a heating mode and a cooling mode, and wherein the wireless thermostat is configured to transmit a heating mode command via the transmitter to the wireless receiver of the mini-split HVAC unit to set the mini-split HVAC unit to the heating mode.
17. The wireless thermostat of claim 16 , wherein the wireless thermostat is configured to selectively transmit a cooling mode command via the transmitter to the wireless receiver of the mini-split HVAC unit to set the mini-split HVAC unit to the cooling mode.
18. A method for controlling a mini-split system HVAC unit via a thermostat that is located remotely from the HVAC unit, the mini-split HVAC unit including an onboard temperature sensor for sensing a temperature local to the mini-split HVAC unit and an onboard thermostatic controller operatively coupled to the onboard temperature sensor, the onboard thermostatic controller configured to store an onboard temperature setpoint and to thermostatically control the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the onboard temperature setpoint, the mini-split HVAC unit further including a wireless receiver for receiving an updated onboard temperature setpoint, the method comprising:
determining an updated onboard temperature setpoint based at least in part on a comparison between an air temperature sensed by a thermostat temperature sensor of the thermostat and a thermostat temperature setpoint stored by the thermostat; and
transmitting the updated onboard temperature setpoint to the wireless receiver of the mini-split HVAC unit so that the onboard thermostatic controller of the mini-split HVAC unit subsequently thermostatically controls the mini-split HVAC unit in a manner that drives the local temperature sensed by the onboard temperature sensor towards the updated onboard temperature setpoint.
19. The method of claim 18 , wherein the updated onboard temperature setpoint is different from the thermostat temperature setpoint.
20. The method of claim 18 , further comprising not transmit the updated onboard temperature setpoint to the wireless receiver of the mini-split HVAC unit when the comparison reveals a difference between the air temperature sensed by the thermostat temperature sensor and the thermostat temperature setpoint is less than a predetermined amount.