TROUBLESHOOTING
Reset Operation
Note: When thermostat is reset, installer configuration menu settings and programming will reset to factory settings.
If a voltage spike or static discharge blanks out the display or causes erratic thermostat operation, you can reset the thermo- stat by removing the wires from terminals R and C (do not short them together) and removing batteries for 2 minutes. After resetting the thermostat, replace the wires and batteries. If the thermostat has been reset and still does not function correctly contact your heating/cooling service person or place of purchase.
Note: Be sure to review the installer configuration menu settings.
To reset the programming, clock and configuration settings, press the and and SYSTEM keys simultaneously. The ther- mostat should go blank and then all segments will be displayed momentarily.
Symptom | Possible Cause | Corrective Action | |
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No Heat/No Cool/No Fan | 1. | Blown fuse or tripped circuit breaker. | Replace fuse or reset breaker. |
(common problems) | 2. | Furnace power switch to OFF. | Turn switch to ON. |
| 3. | Furnace blower compartment door or | Replace door panel in proper position to engage safety |
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| panel loose or not properly installed. | interlock or door switch. |
| 4. | Loose connection to thermostat or system. | Tighten connections. |
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No Heat | 1. | Pilot light not lit. | |
| 2. | Furnace | Many furnaces have safety devices that shut down when |
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| may also be intermittent. | a |
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| contact the furnace manufacturer or local HVAC service |
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| person for assistance. |
| 3. | Heating system requires service or | Diagnostic: Set SYSTEM Switch to HEAT and raise the |
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| thermostat requires replacement. | setpoint above room temperature. Within a few seconds |
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| the thermostat should make a soft click sound. This sound |
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| usually indicates the thermostat is operating properly. If |
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| the thermostat does not click, try the reset operation listed |
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| above. If the thermostat does not click after being reset |
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| contact your heating and cooling service person or place |
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| of purchase for a replacement. If the thermostat clicks, |
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| contact the furnace manufacturer or a HVAC service |
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| person to verify the heating is operating correctly. |
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No Cool | 1. | Cooling system requires service or | Same as diagnostic for No Heat condition except set the |
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| thermostat requires replacement. | thermostat to COOL and lower the setpoint below the |
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| room temperature. There may be up to a five minute delay |
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| before the thermostat clicks in Cooling. |
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Heat, Cool or Fan | 1. | Possible short in wiring. | Check each wire connection to verify they are not shorted |
Runs Constantly | 2. | Possible short in thermostat. | or touching together. No bare wire should stick out from |
| 3. | Possible short in heat/cool/fan system. | under terminal block. Try resetting the thermostat as de- |
| 4. | FAN Switch set to Fan ON. | scribed above. If the condition persists the manufacturer |
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| of your system or service person can instruct you on how |
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| to test the Heat/Cool system for correct operation. If the |
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| system operates correctly, replace the thermostat. |
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Thermostat Setting & | 1. | Thermostat thermometer setting | The thermometer can be adjusted +/- 4 degrees. See |
Thermostat Thermometer |
| requires adjustment. | Temperature Display Adjustment in the Configuration |
Disagree |
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| Menu section. |
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Furnace (Air Conditioner) | 1. | The location of the thermostat and/or | Digital thermostats provide precise control and cycle |
Cycles Too Fast or Too Slow |
| the size of the Heating System may | faster than older mechanical models. The system turns |
(narrow or wide |
| be influencing the cycle rate. | on and off more frequently but runs for a shorter time |
temperature swing) |
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| so there is no increase in energy use. If you would like |
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| an increased cycle time, choose SL for slow cycle in the |
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| Configuration menu, step 7 (heat) or 8 (cool). If an ac- |
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| ceptable cycle rate is not achieved, contact a local HVAC |
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| service person for additional suggestions. |
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Forgot Keypad |
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| Press the menu key (key will disappear) and hold in for |
Lockout Code |
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| 20 seconds. This unlocks the thermostat. |
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Blank display any or keypad | 1. Voltage Spike or static discharge | Use the Reset Operation shown above. | |
not responding |
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HOMEOWNER HELP LINE:
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