Hi All, After giving our elderly (17yrs old) Cental Heating system a much needed = service/overhaul(boiler was flat out all the time whatever position the = boiler stat was set to-so we got hotter as the night progressed) I was a = bit surprised to find with a new boiler stat fitted that even on the = lowest temp setting the house was still too warm 28-30 C.A friend in the = trade suggested that as we had recently installed modern double-glazed = windows and doors,we were finally getting the rooms warm without heating = up all the draughts and cold air that used to be part of the house,the = room temp was only now becoming apparent.We did not even have a room = stat fitted,so fitting one would allow us to get a lower overall temp = out of the system.The Glow Worm balanced-flue boiler only runs 6 = rads,the H.W. taken care of by an incredibly reliable Corvec-Britony = unit. So a room stat was fitted and a new wall-mounted timer as well(the old = electric clock style unit fell apart while I was setting the time = segments).We are clearly feeling the benefits from this relatively cheap = upgrade but there is an issue with the original boiler wiring and = thermostat overrun which I would like anyone in the NG to give any = comments on,(my pal is in the Canaries,so I don't want to run up a = massive phone bill for what is maybe an issue that is easily explained). The original pump wiring was not through the boiler = stat/pump overrun but directly from the timer switch, so pump was = running all the time boiler was on.I have wired the pump now through the = new boiler stat/pump overrun - exactly how it shows in the original = boiler service diagram.Is the pump overrun circuit designed to run on = for a set time after each firing of the burner or only at a pre-arranged = heat setting?I have only just finished the work and it seems that the = pump only overruns when the system is quite hot.I am now not sure = whether the original pump wiring was incorrect or was the pump running = all the time actually intended?We also have always had the 1st rad in = the circuit(small bedroom nearest to boiler) running seemingly hotter = than all the others ever since moving into the house 15years ago,I = wonder if again wiring the pump to "always on" was an attempt by the = original installer to even the heat out in all the rads. OK men----------------any comments?
Many Thanks T.R.K.