Just had a new Vaillant Eco Tech Plus 630 boiler fitted and the heating engineer has set the flow temp at 60 degrees from the boiler. Have 3 manifolds, 10 loops, all with adjustable mixing valves to control the mixed underfloor and under screed zones. The old boiler didn't have a programmable flow temperature, set with an adjustable dial. Having searched various subjects on this forum could I have your opinions on:
1) It is more efficient to leave the UFH heating on 24 / 7. I have set it up to run from 04.00 to 20.00.
2) Can the flow temperature be decreased - does making the return temperature lower make the boiler more efficient
3) I have bled the manifolds twice and removed quite a bit of air - fine yesterday afterwards as the system was running at around 1.1 bar. However not running overnight, I assume the cooling water has dropped the pressure, as a result the boiler had switched itself off this morning, it was at 0.3 bar. Topped up the boiler a little and running again at 1.5 bar. Is it trial and error to reach the correct pressure
4) Any other tips.
1) It is more efficient to leave the UFH heating on 24 / 7. I have set it up to run from 04.00 to 20.00.
2) Can the flow temperature be decreased - does making the return temperature lower make the boiler more efficient
3) I have bled the manifolds twice and removed quite a bit of air - fine yesterday afterwards as the system was running at around 1.1 bar. However not running overnight, I assume the cooling water has dropped the pressure, as a result the boiler had switched itself off this morning, it was at 0.3 bar. Topped up the boiler a little and running again at 1.5 bar. Is it trial and error to reach the correct pressure
4) Any other tips.