H
HowardML
I'd like to try and get a better handle on what is ailing our central heating system. The problem is with the underfloor heating circuit.
The main system is a heat only Ideal Mexico HE30, with conventional expansion tank and hot water cylinder. It serves a hot water circuit, the house rads and the extension u/floor system. It has a Drayton (Ikon branded) LP 522 programmer which we know works. The room thermostat is new. It is a Drayton Digistat. This part of the system works just fine.
The underfloor heating is a nightmare. It runs (or rather doesn't) on a separate circuit with a separate zone valve. New Drayton Digistat RF3 system
The original installation was a botched job about 10 years ago. The underfloor circuit was an extension added to the existing system. We have just had the wiring sorted out and the wireless digistats/programmer installed in an attempt to make the system electrically safe (believe me it was a wiring tangle and mess) and to give us separate control of the two heating circuits - both timing and temperature.
The zone valve for the underfloor seemed to be faulty - the actuator motor was replaced last week too. The valve itself was checked and is opening and closing just fine
We have a local heating company engaged on this. I'm not trying to second guess them but I do need to get to the bottom of this in my own mind. I've called them again about this (well e-mail actually)
This morning (Thursday) I was awake early and I heard a thump from the boiler as the u/floor system came on (an hour earlier than the main system). The boiler ignition circuit was on (ICOS main board - light flashing) but the boiler had not lit (light should be on constantly). The boiler did light twice for a few moments and then switched back to "stand-by". This is an issue we have seen before and it was what partly prompted the re-wire of the system. The digistat was showing demand.
We overrode the system to bring the main heating circuit on early and the boiler lit, has stayed alight and we think the u/floor is warming up slowly (it has always been slow).
The main circulation pump seems not to be wired to the boiler. Our heating company tell me that they could not see a circuit within the boiler to do this. Only one pump (Grundfoss) for all three circuits (two heating and hot water)
Further history - the boiler was completely rebuilt by Ideal last year - the only surviving parts are the fan system and casing. It seems to be working OK. The wiring was tidied and the digistat controls were done within the last week after a heating failure during the early autumn as we restarted the system.
We discovered during the re-wire diagnostics that the two separate wired room stats had been botched as well. They were cross-wired in a way so that the underfloor stat only worked when the main system was running (if that makes sense). They are now on completely separate electrical circuits.
I feel lost and powerless in all of this. I know it is a job for the professionals but I do need to understand more.
Any advice appreciated. I'm not going to blunder in with my heating company but what we have done should have sorted this out but clearly someone is missing something - probably me.
The main system is a heat only Ideal Mexico HE30, with conventional expansion tank and hot water cylinder. It serves a hot water circuit, the house rads and the extension u/floor system. It has a Drayton (Ikon branded) LP 522 programmer which we know works. The room thermostat is new. It is a Drayton Digistat. This part of the system works just fine.
The underfloor heating is a nightmare. It runs (or rather doesn't) on a separate circuit with a separate zone valve. New Drayton Digistat RF3 system
The original installation was a botched job about 10 years ago. The underfloor circuit was an extension added to the existing system. We have just had the wiring sorted out and the wireless digistats/programmer installed in an attempt to make the system electrically safe (believe me it was a wiring tangle and mess) and to give us separate control of the two heating circuits - both timing and temperature.
The zone valve for the underfloor seemed to be faulty - the actuator motor was replaced last week too. The valve itself was checked and is opening and closing just fine
We have a local heating company engaged on this. I'm not trying to second guess them but I do need to get to the bottom of this in my own mind. I've called them again about this (well e-mail actually)
This morning (Thursday) I was awake early and I heard a thump from the boiler as the u/floor system came on (an hour earlier than the main system). The boiler ignition circuit was on (ICOS main board - light flashing) but the boiler had not lit (light should be on constantly). The boiler did light twice for a few moments and then switched back to "stand-by". This is an issue we have seen before and it was what partly prompted the re-wire of the system. The digistat was showing demand.
We overrode the system to bring the main heating circuit on early and the boiler lit, has stayed alight and we think the u/floor is warming up slowly (it has always been slow).
The main circulation pump seems not to be wired to the boiler. Our heating company tell me that they could not see a circuit within the boiler to do this. Only one pump (Grundfoss) for all three circuits (two heating and hot water)
Further history - the boiler was completely rebuilt by Ideal last year - the only surviving parts are the fan system and casing. It seems to be working OK. The wiring was tidied and the digistat controls were done within the last week after a heating failure during the early autumn as we restarted the system.
We discovered during the re-wire diagnostics that the two separate wired room stats had been botched as well. They were cross-wired in a way so that the underfloor stat only worked when the main system was running (if that makes sense). They are now on completely separate electrical circuits.
I feel lost and powerless in all of this. I know it is a job for the professionals but I do need to understand more.
Any advice appreciated. I'm not going to blunder in with my heating company but what we have done should have sorted this out but clearly someone is missing something - probably me.
