Honeywell thermostat troubleshooting

The troubleshooting system allowing to reveal malfunctions and find ways of their removal on one`s own is assigned to many advantages of the American thermostats Honeywell. The table reflecting all the key aspects of Honeywell thermostat troubleshooting is presented below.

Honeywell basic series thermostat troubleshooting

ProblemPossible CauseSolution
Excessive noiseIf there is an antihum spring, it is not touching the throttling plate.Reposition spring to touch throttling plate.
Stick an adhesive paper dot on the throttling plate across the hinge between the two rivets so that the dot is directly below the “A" in MAX printed on the bimetal.
If there is no antihum spring or cone, the adhesive paper dot has fallen off of the throttling plate.Stick an adhesive paper dot on the throttling plate as described above.
Air leak in restrictor block and filter assembly.Use a bubble solution to locate the leak and repair it.
Replace the restrictor block assembly and filter.
Install Stiffener Plate 14004609-001 on the backplate.
Oil or moisture in lines.Replace the restrictor block assembly and filter. Also ensure that the air supply to the thermostat is dry and clean.
Slow responseInadequate air flow caused by a partially clogged restrictor block assembly and/or filter cartridge.Replace restrictor block assembly and/or filter.
Thermostat instabilitySystem gain is too high.Move throttling range adjustment toward MAX position and then recalibrate.
Inaccurate readingsInaccurate calibration.Recalibrate thermostat.
Metal cover setscrews over-tightened.Turn setscrews in.
Backplate over-tightened.Install Stiffener Plate 14004609-001 on the backplate.
Thermostat not switching over at changeover pressurePressure at thermostat is incorrect.Readjust compressed airline to proper switching pressure.
Switchover pressure in thermostat is incorrectly calibrated.Turn switchover adjustment screw to recalibrate pressure for proper switching.
Air leakBranch line plug leaking.Install Plug 14002172.
Cannot calibrate thermostatOil or moisture in lines.Replace the restrictor block assembly and filter. Also ensure that the air supply to the thermostat is dry and clean.

Honeywell YRTH series thermostat troubleshooting


Display is blankMake sure fresh AA alkaline batteries are properly installed (see page 7).
Cannot change system setting to Cool
Check Function 0170: System Type to make sure it is set to match your heating and cooling equipment (see page 16).
Fan does not turn on when heat is required
Check Function 0180: Heating Fan Control to make sure it is set to match your heating equipment (see page 17).
Heating system is running in cool mode
Check Function 0170: System Type to make sure it is set to match your heating and cooling equipment (see page 16).
Red light is onIf thermostat is in Emergency Heat mode the red light is normal. It shows that the thermostat is in emergency heat mode. If thermostat is not in Emergency Heat mode, contact a qualified service con- tractor for repair.

Honeywell VisionPRO series thermostat troubleshooting


ProblemsCause/Solutions
Screen is blank• Check circuit breaker and reset if necessary.
• Make sure power switch at heating and cooling system is on.
• Make sure furnace door is closed securely.
• If thermostat is battery powered, make sure fresh AA alkaline batteries are installed correctly (see page 32).
Screen is difficult to read• Change screen brightness using Preferences menu (see page 26).
Red light is on• If thermostat is in Emergency Heat mode, the red light is normal. It shows that the thermostat is in Emergency Heat mode.
• If thermostat is not in Emergency Heat mode, an alert is active. Check message on the thermostat screen.
Heating or cooling system does not respond





• Touch SYSTEM to set system to Heat. Make sure the temperature is set higher than the Inside temperature.
• Touch SYSTEM to set system to Cool. Make sure the temperature is set lower than the Inside temperature.
• Check circuit breaker and reset if necessary.
• Make sure power switch at heating & cooling system is on.
• Make sure furnace door is closed securely.
• If “Wait” is displayed, the compressor protection timer is on. Wait 5 minutes for the system to restart safely, without damaging the compressor.

Honeywell W series thermostat troubleshooting


SymptomPossible CauseAction
The battery indicator is on continuously.The battery is either dead or not installed.Install or replace the battery.
The battery indicator is flashing with a steady on-off pulse.The battery is weak.Replace the battery.
The battery indicator appears to flash momentarily every 10 seconds.The battery is good.No action is required.
The online indicator is illuminated.The telephone module is currently in a dial-in or dial-out sequence.Wait for the call to end.
The auxiliary input indicator is illuminatedThe Telephone Access Module detected a contact closure on the auxiliary input terminals.Determine the cause of the contact closure. Remedy the problem according to the contact manufacturer instructions.
When I dial into the Telephone Access Module, it indicates “The system is not responding.”The Telephone Access Module is not receiving data from the thermo- stats.Make sure all connections between the communicating devices are good. Contact your installer.
My password is not working.You may have forgotten your pass code.Press and hold the passcode reset switch for ten seconds. The pass code will be reset to 1-2-3-4. Retry with the default pass code.