Source: https://insight.rpxcorp.com/pat/US20120318138A1
Timestamp: 2019-11-20 16:45:35
Document Index: 418017966

Matched Legal Cases: ['Application No. 20090140062', 'Application No. 20090143880', 'Application No. 20090143918', 'Application No. 20090143916', 'Application No. 20090143879', 'Application No. 20090140056']

Patent US 20120318138A1
US 10,457,537 B2
It is contemplated that the HVAC controller(s) 18 may be configured to control the comfort level in the building or structure by activating and deactivating the HVAC component(s) 6. The HVAC controller(s) 18 may be configured to control the HVAC component(s) 6 via a wired or wireless communication link 20. In some cases, the
HVAC controller(s) 18 may be a thermostat, such as, for example, a wall mountable thermostat, but this is not required in all embodiments. In some embodiments, the one or more HVAC controllers 18 may include multiple zone controllers, each monitoring and/or controlling the comfort level within a particular zone in the building or other structure. An illustrative HVAC controller, which is not meant to be limiting in any way, is disclosed in: US Published Patent Application No. 20090140062, entitled “HVAC CONTROLLER THAT SELECTIVELY REPLACES OPERATING INFORMATION ON A DISPLAY WITH SYSTEM STATUS INFORMATION”; US Published Application No. 20090143880, entitled “HVAC CONTROLLER WITH CONTEXT SENSITIVE HELP SCREENS”; US Published Application No. 20090143918, entitled “METHOD AND APPARATUS FOR CONFIGURING AN HVAC CONTROLLER”; US Published Application No. 20090143916, entitled “HVAC CONTROLLER HAVING A PARAMETER ADJUSTMENT ELEMENT WITH A QUALITATIVE INDICATOR”; US Published Application No. 20090143879, entitled “HVAC CONTROLLER WITH PARAMETER CLUSTERING”; US Published Application No. 20090140056, entitled “HVAC CONTROLLER WITH QUICK SELECT FEATURE,” the entireties of which are incorporated herein by reference for all purposes.
To determine and set an air filter change threshold value for the HVAC system), first a system user (e.g., installer or HVAC contractor) may install a clean air filter in the system. Next, in response to an indication that a clean air filter has been installed, the controller may instruct the HVAC system to operate in a selected mode or state (Block 210). The HVAC system may be operated in a mode or state in which the fan is “on” and drives air through the air filter. In some cases, this may be a “fan only” mode or state in which the heating and/or cooling element is “off' and only the fan is operated at a selected speed. In other cases, the HVAC system may be operated in a heating mode (e.g., HEAT 1) or a cooling mode (e.g., COOL 2). In another case, the HVAC system may be operated in a ventilation mode. In still other cases, the HVAC system may be operated in a humidifying mode or dehumidifying mode. Typically, the mode or state having the highest fan speed may be selected, but this is not always the case. In some cases, the mode may be selected based on which mode or state may provide the greatest negative impact on equipment life from a dirty filter.
Referring again to FIG. 12, after the blocking panel has been sized to achieve the desired amount of air flow blockage and inserted into the system, the user may select a system mode or state in which to operate the HVAC system (Block 362). The HVAC system may be operated in a mode or state in which the fan is “on” and drives air through the blocking panel and/or air filter. In some cases, this may be a “fan only” state or mode in which the heating and/or cooling element is “off' and only the fan is operated at a selected speed. In other cases, the HVAC system may be operated in a heating mode (e.g., HEAT 1) or a cooling mode (e.g., COOL 2). In another cases, the HVAC system may be operated in a ventilation mode. In still other cases, the HVAC system may be operated in a humidifying mode or a dehumidifying mode. Typically, the mode having the highest fan speed is selected, but this is not always the case. In some cases, the mode may be selected based on which mode may provide the greatest negative impact on equipment life from a dirty filter. The HVAC system may then be operated in the selected mode with the blocking panel to obtain, for example, a differential pressure or other measure related to an amount of flow restriction presented by the blocking panel(Blocks 358 and 362). In some cases, the user may operate the HVAC system in various different modes, obtaining a differential pressure or other measure related to an amount of flow restriction presented by the blocking panel for each mode. In some cases, each time a new measurement is obtained it may replace the previous measurement. Thus, the system differential pressure measurement associated with the at least partially blocked air filter may be based on the last mode in which the HVAC system is operated, but this is not required.
The protocol for setting the air filter change threshold value may be initiated by selecting the button 450 labeled FILTER MONITORING CALIBRATION on the INSTALLER OPTIONS menu screen 410. Selecting the FILTER MONITORING
CALIBRATION button 450 on the INSTALLER OPTIONS menu screen 410 may cause a CALIBRATION menu screen 414 to be displayed (FIG. 14D). The CALIBRATION menu screen 414 may display one or more buttons 466a, 466b labeled with the different filter calibration methods that may be employed by the user to determine and set the air filter change threshold value. For example, as shown in FIG. 14D, the CALIBRATION menu screen 414 may be configured to display a first button 466a labeled CLEAN FILTER CALIBRATION and a second button 466b labeled BLOCKED FILTER CALIBRATION. In some cases, the CALIBRATION menu screen 414 may be configured to display a user prompt 470 that may prompt the user to select a calibration method from the different calibration method options that may be displayed by the CALIBRATION menu screen 414. The CALIBRATION menu screen 414 may be also configured to display a HELP button 474 and/or a CANCEL button 478 which, if selected, may return the user to the previous INSTALLER OPTIONS menu screen 410 or home screen 402. Selection of the calibration method may be initiated by pressing either the CLEAN FILTER CALIBRATION button 466a or the BLOCKED FILTER CALIBRATION button 466b. In this example, as shown in FIG. 11D, the BLOCKED FILTER CALIBRATION METHOD button 466b is highlighted indicating to the user that the BLOCKED FILTER METHOD option has been selected. Selection of the BLOCKED FILTER CALIBRATION METHOD may be confirmed and/or initiated by pressing the NEXT button 482 displayed on the CALIBRATION menu screen 414.
In many cases, the same mode is used each time the air filter monitor 34 is requested to measure the differential pressure across the air filter 30.In some cases, the controller 18 may place the HVAC system in a “fan only” mode prior to commanding the air filter monitor 34 to measure the differential pressure across the air filter 30. In a “fan only” mode, all HVAC system equipment except for the fan may be placed in the “off state,” and for a zoned system, all dampers may be placed in the “open” position. In some cases, the heating or cooling element may be turned “off” In other cases, the heating element and/or cooling element may be turned on. In any event, the controller 18 may be adapted to turn on the fan or blower 22. The fan or blower 22 may be operated at the same fan speed each time a differential pressure measurement is made. For variable speed fans, the fan speed may be adjusted such that the fan is operated at the highest fan speed available, but this is not required. What may be desirable is that the fan speed setting should be consistent for each measurement, and all other variable (e.g. the on or off set of the heating and/or cooling element, the damper positions, etc., should also be constant. Thus, it may provide a more consistent and accurate differential pressure measurement over time.
As previously discussed, the differential pressure measurement (or other measure related to the amount of air flow restriction presented by the air filter) may be used to evaluate the status of the air filter 30. In some cases, the controller 18 and /or processor 44 may be configured with an algorithm that compares the differential pressure measurement as measured by the air filter monitor 34 during operation of the HVAC system 4 to the air filter change threshold value. This comparison may then be used to determine the current status of the air filter.
In some cases, once in the “Change Filter Soon” state, after a predetermined period of time set by the controller 18, the controller 18 may change the filter status from
“Change Filter Soon” to “Change Filter Now”, and may change the color from yellow to red. In some cases, the “snooze” function may no longer be available to the user.
Bisson, Reed, Hoglund, Steven, Ragland, Amy, Dean-Hendricks, Barbara, Goh, Christopher