Symptom Possible Cause Corrective Action
Thermostat Setting and Thermostat 1. Thermostat thermometer setting requires The thermometer can be adjusted +/- 5 degrees.
Thermometer Disagree adjustment. See Temperature Display Adjustment in the
Operating Manual under Configuration.
Thermostat Display Shows CHCK PAD, 1. Thermostat service indicators. These indicators can be reset or modified in the
CHNG FLTR, CALL SERV UV, CALL SERV service button menu (see pg. 8).
TROUBLESHOOTING
11
Why does the system run with the
setpoint and room temperature the
same?
How do I temporarily Override the
program and Hold Til Timing?
Aux. = Auxiliary Heat or the second stage of heat in the Heat mode. This is energized
In cooling, as the room temperature falls you will eventually reach the setpoint
temperature. The system will continue to run until it reaches the low side of the
temperature setting. As an example: If set to 78 degrees with the room temperature
falling the thermostat will continue to call for cool as the temperature decreases in the
following manner. 78.9, 78.8, 78.7, 78.6, 78.5, 78.4, 78.3, 78.2, at approximately 78.2
the thermostat will quit calling for cool. This is why it is not unusual for the room
temperature and set temperature to read the same but the system continues to run.
The amount of time it takes for the system to shut off is dependent on system sizing,
thermostat location, etc. Note: The thermostat display only displays whole numbers.
Internally the thermostat calculates decimals.
In heating as the room temperature increases the system will continue to run until the
thermostat reaches the high side of the temperature setpoint.
Digitals are engineered to a specific response rate. Compared to a thermometer it will
seem slow. When left to acclimate and control temperature it will provide precise
temperature control on a properly sized system.
Any time your program is running and you would like to override it for a specific
amount of time, press
or until the temperature you want is displayed. The
display will indicate HOLD, and the number of hours remaining in the hold period will
be indicated with the word HRS. To adjust the length of time for the override, press
TIME FWD or TIME BACK. The time you select will become the new number of hours
for the Hold Til timing. Once your time is selected, let the thermostat revert back to
normal operation on its own to accept the change.
Many furnaces have safety devices that shut the system down when a lock-out
condition occurs in the furnace. If the thermostat is turned off or the call for heat is
cancelled (by lowering and then raising the set temperature) the furnace may start
operating again. A diagnostic to see if the thermostat is operating when the room
temperature is below the thermostat setting (in heat) is to lower the setting below the
room temp. Within about 3 seconds the thermostat should make a soft click sound.
This sound is the thermostat turning off the call for heat and usually indicates the
thermostat is operating properly. If the thermostat does not click you would be
suspicious of the thermostat and try resetting it by following it’s reset operation. If the
thermostat does not click after being reset contact your heating and cooling service
person or place of purchase for a replacement. If the thermostat clicks and the heat
works intermittently contact the furnace manufacturer or local service person. They
will want to observe the condition when it is not working.
You can raise and lower the temperature a few degrees above and below the room
temperature and each time expect to hear the thermostat click on and off within a few
seconds. If it clicks, it is operating properly.
FAQs
Why is the temperature change
display so slow?
What is the thermostat Click Test?