Hi,
I have a Vaillant EcoTEC Plus 637 in my house which has 4 beds and a living room with 6 rads total. I also have underfloor heating running off the boiler and hot water in an unvented system.
My issue is that when the room stat for the radiators calls for heat the boiler fires but never reaches the target flow temp of 69 degrees. It will burn to roughy 45 degrees and stay there for a few mins, cut out and fire back up again. But for the underfloor heating the boiler fires up and burns close to the target flow temp and stays on between 55 and 70 until the room thermostat turns it off.
To me it doesn’t make sense. The radiators take an age to heat the rooms and they never get overly hot to the touch. I have bled the rads, checked the pressure etc and all looks fine.
Any suggestions would be appreciated.
Many thanks!
I have a Vaillant EcoTEC Plus 637 in my house which has 4 beds and a living room with 6 rads total. I also have underfloor heating running off the boiler and hot water in an unvented system.
My issue is that when the room stat for the radiators calls for heat the boiler fires but never reaches the target flow temp of 69 degrees. It will burn to roughy 45 degrees and stay there for a few mins, cut out and fire back up again. But for the underfloor heating the boiler fires up and burns close to the target flow temp and stays on between 55 and 70 until the room thermostat turns it off.
To me it doesn’t make sense. The radiators take an age to heat the rooms and they never get overly hot to the touch. I have bled the rads, checked the pressure etc and all looks fine.
Any suggestions would be appreciated.
Many thanks!