There are various reasons this could be the case including if the machine is not properly adjusted.
Central heating room thermostat not working.
Continue to the thermostat wiring section.
Is your thermostat in the wrong place.
Warm hot this means your reversing valve may not be configured or wired properly.
When your thermostat says one temperature and you know the room is another it may be dirty tilted on the wall or located where it can t get a proper reading.
Thermostat does not control temperature.
Heating thermostats work by monitoring the average temperature of your home and sending a signal to a boiler to ensure it s never too hot or too cold.
A central heating thermostat is a set of controls used to regulate the output of your heating system to make sure a comfortable temperature is maintained.
Central heating problems can often be down to a broken thermostat that won t work.
If the room is too warm or too cold the thermostat requests heat or air depending on the season.
Crank it right up and see if your boiler starts working again.
If your room thermostat is set below 21 degrees it may stop your heating from turning on altogether.
Cold this means your thermostat is cooling correctly but the heating isn t working properly.
2 remove the thermostat s cover.
The thermostat detects the temperature of the room and compares it to the desired temperature setting.