HVAC control
A method of monitoring HVAC usage includes: maintaining a data structure in an on board memory of a programmable usage monitoring HVAC thermostat; receiving an initiation signal from a relay; receiving a termination signal from the relay; and updating the data structure by adding a duration in units of time to an accumulated time associated with the relay to keep a log of the elapsed time a function associated with the relay was operative. A programmable usage monitoring HVAC thermostat comprising, a user interface; a microprocessor coupled to the user interface; and a firmware upgradeable memory coupled to the microprocessor.
1 . A method of monitoring HVAC usage, comprising:
maintaining a data structure in an on board memory of a programmable usage monitoring HVAC thermostat;
receiving an initiation signal from a relay;
receiving a termination signal from the relay; and
updating the data structure by adding a duration in units of time to an accumulated time associated with the relay to keep a log of the elapsed time a function associated with the relay was operative.
2 . The method of monitoring HVAC usage of claim 1 , wherein the accumulated time associated with the relay is recorded each initiation-termination cycle.
3 . The method monitoring HVAC usage of claim 1 , wherein the accumulated time associated with the relay is recorded each day.
4 . The method of monitoring HVAC usage of claim 1 , wherein the accumulated time associated with the relay is recorded each week.
5 . A machine readable medium, comprising a program for performing the method of claim 1 .
6 . A method of servicing an HVAC system, comprising:
setting a programmable usage monitoring HVAC thermostat into a service state; and
setting a mode of the programmable usage monitoring HVAC thermostat to run in a cooling stage 1 , a cooling stage 2 , a heating stage 1 or a heating stage 2 to verify that the mode is operating properly
7 . The method of servicing an HVAC system of claim 6 , further comprising repeating setting the mode automatically.
8 . The method of servicing an HVAC system of claim 7 , further comprising repeating setting the mode automatically until all available modes are polled as verified.
9 . A programmable usage monitoring HVAC thermostat, comprising:
a user interface;
a microprocessor coupled to the user interface; and
a firmware upgradeable memory coupled to the microprocessor.
10 . The programmable usage monitoring HVAC thermostat of claim 9 , wherein the firmware upgradeable memory includes an erasable programmable read only memory.
11 . The programmable usage monitoring HVAC thermostat of claim 9 , wherein the firmware upgradeable memory includes two sectors, wherein 1) a first sector is mirrored by a second sector during operation in a first mode, 2) the first sector can be upgraded while the second sector is not upgraded during operation in a second mode, 3) the first sector can be operationally connected to the microprocessor in a third mode and 4) the second sector can be operationally connected to the microprocessor in a fourth mode, and wherein the firmware upgradeable memory can be reversibly switched from a first member selected from the group consisting of the first mode, the second mode, the third mode and the fourth mode to a second member selected from the group consisting of the first mode, the second mode, the third mode and the fourth mode, thereby providing a firmware upgradeable memory with hot swappable sectors and a firmware reversion capability.
12 . A method of operating an HVAC system, comprising:
enabling an open interlock function of a programmable usage monitoring HVAC thermostat;
detecting that an interlock is open;
measuring a period of time during which the interlock remains open; and
when the period of time exceeds a preset threshold, displaying an open notice.
13 . The method of operating an HVAC system of claim 12 , further comprising, when one or more of the period of time exceeds a preset threshold, forcing the HVAC system to an OFF state until the interlock is closed.
14 . The method of operating an HVAC system of claim 12 , wherein detecting includes sensing that a door is open.
15 . A method of operating an HVAC system, comprising:
enabling an overload function of a programmable usage monitoring HVAC thermostat;
measuring a period of time during which the programmable usage monitoring HVAC thermostat is calling for cooling or heating; and
when the period of time exceeds a preset threshold, displaying an overload notice.
16 . The method of operating an HVAC system of claim 15 , further comprising, when the period of time exceeds the preset threshold, forcing the HVAC system to an OFF state.
17 . A system, comprising:
a programmable usage monitoring HVAC thermostat including
a user interface,
a microprocessor coupled to the user interface and
a memory coupled to the microprocessor; and
a temperature sensor coupled to the programmable usage monitoring HVAC thermostat, the temperature sensor located in an HVAC duct.
18 . The system of claim 17 , further comprising i) an internal temperature sensor located in the programmable usage monitoring HVAC thermostat and a remote sensor not located in the HVAC duct.
19 . A method of operating an HVAC system, comprising:
monitoring periodically a plurality of relays coupled to a programmable usage monitoring HVAC thermostat; and
when one or more of the plurality of relays is found to be in a non-conforming state, displaying a malfunction notice.
20 . The method of operating an HVAC system of claim 19 , further comprising, when one or more of the plurality of relays is found to be in a nonconforming state, forcing the HVAC system to an OFF state.