Vaillant boiler - central heating downstairs higher temperature than should be but upstairs not on at all which is correct- what is the problem
Boiler keeps firing every 5 minutes to keep boosting the temperature.
It is set to be 20 degrees now but it is now 24 degrees
We have not changed any of the settings and it was working perfectly. Then last evening the temperature downstairs kept on rising above the set temperature.
The room stats are in the hall and this is where the temperature is set. What are TRV's. It is very worrying that the temperature continues to rise above the set temperature but only downstairs