Can anyone talk me through the cycles of a condensing boiler? We have two system boilers fitted in tandem at our church. I was insulating the pipes on Saturday (the ones the installers couldn't be bothered to) while the boilers ran. One boiler was running flat out, and the other was on low flame. Then they would swap over with a several minutes of both flat out. The boilers were running with maximum load - the main church building, plus the meeting rooms and kitchen. I would have thought they should be going flat out permanently. Do they need to have a rest occasionally? Cheers Les
I can only comment on my condensing boiler and that goes to high flame until the system gets warm then it goes to low flame i.e modulating gas valve it is normal for this to happen as far as your boilers it looks like one boiler is getting the cooler return water and that is making it fire on full for a spell the boilers will shut down when the place gets warm enough