I have a 12-year Vaillant ecoTEC Plus 438 condensing boiler that is used to heat up 19 radiators.
When the heating is turned on at the start of the morning, all radiators become hot with the 3 furthest radiators from the boiler being last to heat up. Once the set temperature on the room thermostat has been reached, the boiler turns off as expected.
When the room temperature drops and the room thermostat fires the boiler, the three furthest radiators only become luke warm, not hot like the other radiators. We have not had this problem in the past, only since yesterday since we have turned on our central heating.
Can anyone advise why this is happening and what can be done to resolve this problem? Nothing has been altered to cause this to happen.
When the heating is turned on at the start of the morning, all radiators become hot with the 3 furthest radiators from the boiler being last to heat up. Once the set temperature on the room thermostat has been reached, the boiler turns off as expected.
When the room temperature drops and the room thermostat fires the boiler, the three furthest radiators only become luke warm, not hot like the other radiators. We have not had this problem in the past, only since yesterday since we have turned on our central heating.
Can anyone advise why this is happening and what can be done to resolve this problem? Nothing has been altered to cause this to happen.
Last edited: