Posts tagged: honeywell programmable thermostat troubleshooting

Thermostat Troubleshooting

Thermostat problems can arise from a number of common problems.  Thermostat troubleshooting is usually the first place you start when your heating or cooling system isn’t working as it should. This is simply because thermostats are relatively easy to troubleshoot and if found to be the cause of all the trouble they are relatively simple and more often than not, less expensive to replace. Most DIYers and handymen will be able to replace a malfunctioning thermostat and just about everyone is able to embark on some thermostat troubleshooting thanks to this guide.

Getting started

Before we start with the thermostat troubleshooting exercise, it is necessary to clarify some terms. The setpoint temperature is the temperature the thermostat has been set it. The room temperature is the actual temperature. The idea is to have them as close as possible.

The thermostat will be connected to heating and cooling equipment, one of which will always be on if the thermostat is doing its job correctly. Many times in warmer climates the thermostat will just be connected to an air conditioner which will be on when the room temperature is above the set point temperature and vice versa.

  • Turn off all power before you begin just to be safe.
  • Confirm that the thermostats thermometer is working correctly by comparing it to the results on another thermometer, preferably a digital one whose results are generally more accurate.
  • To confirm if the thermostat is battery powered or not open up the cover. There are a number of connections. The thermostat is battery powered if the ‘C’ connection has no wire.
  • Check that the batteries are the correct ones and replace if necessary.
  • Ensure that there is power supply to the thermostat by checking that the backlight is on. At the same time double check that both the heating and cooling equipment is switched on.
  • Some thermostats do not use batteries; instead they gain their energy from the equipment that they regulate. If there is a malfunction with the heating system it will look as though the thermostat is faulty.
  • If the erratic heating is not sudden, it may simply mean that the location of the thermostat is not ideal. If it is located in a draughty area or a particularly warm area this can affect the way it behaves.

If you have chosen to replace the device after some in depth thermostat troubleshooting remember to look for one that uses power from the air conditioner or heating system, instead of an independent power source, that also comes with a battery backup. This is called power stealing technology. The reason for this is because programmable thermostats with their own power supply will lose their programs every time there is a power cut. Reprogramming a thermostat that may have a series of complex settings can be tedious. Having a better backup will eliminate this problem so that even when the equipment is out of action due to lack of power, the programmes are retained.