Hello!
This is really a post to help satisfy my curiosity more than anything else, and perhaps help out with a long-running problem that our plumber hasn't so far been able to fix completely. I'm just wondering whether I might be on the right track.
I'm a tenant in a property that has a Halstead Ace High combi boiler. Since we moved in three months ago we've had all kinds of problems with the thing, requiring tons and tons of plumber callouts. We've had a holed diaphragm, a busted expansion vessel, and now (this has been going on the whole time, actually, alongside other problems), the boiler simply fails to ignite with no advanced warning and for no apparent reason. When we turn on a hot tap / the heating, the fan starts, the boiler registers the demand for hot water, but it doesn't ignite. It does not lock out or overheat. Pressure has been steady at exactly 1.45 bar for the last week and it's failed several times during that period.
The plumber has had to come out a few times, and has usually managed to get the thing firing again, but usually by way of vague fiddling rather than actually doing anything definitive, and it usually happens again within a few days. He doesn't know what the actual problem is, apart from it being a crappy boiler.
Anyway, by mistake the other day I discovered that, when it fails to ignite, if you leave the hot tap open for quite a long time (3-4 minutes), the boiler does light. I've tried this successfully twice in a row, so it could just be a fluke. But my theory at this point is perhaps that one of the thermistors is faulty. Would that cause this kind of behaviour? I was thinking perhaps that it works when the tap's left on because leaving the tap open with the boiler 'off' might be flushing tons of cold water through it, cooling down the thermistor and 'resetting' it (I don't really know what I'm on about as you can see). Does this sound possible/likely? I know thermistors don't tend to fail that often but does it sound possible? What else might it be, if not?
I know it's a simple enough job to test a thermistor with a multimeter but I have not opened the boiler case or looked inside, and will not be doing so. I want hot water but not enough to do illegal gas work or put myself, my gf or our neighbours in danger of CO leaks or anything like that. What I want is to be able to put this possibility to the plumber the next time he (inevitably) comes around and not feel like a plum for doing so. I would do this diplomatically of course; I don't want to seem like I'm teaching my grandmother to suck eggs!
Finally, I know the real solution is "chuck out that pile of crap and get a decent boiler", but as mentioned, we're tenants. And have you ever tried to convince a landlord to spend the thick end of a thousand quid on installing a new boiler when the old one could limp on a bit longer?
Thank you everyone!
This is really a post to help satisfy my curiosity more than anything else, and perhaps help out with a long-running problem that our plumber hasn't so far been able to fix completely. I'm just wondering whether I might be on the right track.
I'm a tenant in a property that has a Halstead Ace High combi boiler. Since we moved in three months ago we've had all kinds of problems with the thing, requiring tons and tons of plumber callouts. We've had a holed diaphragm, a busted expansion vessel, and now (this has been going on the whole time, actually, alongside other problems), the boiler simply fails to ignite with no advanced warning and for no apparent reason. When we turn on a hot tap / the heating, the fan starts, the boiler registers the demand for hot water, but it doesn't ignite. It does not lock out or overheat. Pressure has been steady at exactly 1.45 bar for the last week and it's failed several times during that period.
The plumber has had to come out a few times, and has usually managed to get the thing firing again, but usually by way of vague fiddling rather than actually doing anything definitive, and it usually happens again within a few days. He doesn't know what the actual problem is, apart from it being a crappy boiler.
Anyway, by mistake the other day I discovered that, when it fails to ignite, if you leave the hot tap open for quite a long time (3-4 minutes), the boiler does light. I've tried this successfully twice in a row, so it could just be a fluke. But my theory at this point is perhaps that one of the thermistors is faulty. Would that cause this kind of behaviour? I was thinking perhaps that it works when the tap's left on because leaving the tap open with the boiler 'off' might be flushing tons of cold water through it, cooling down the thermistor and 'resetting' it (I don't really know what I'm on about as you can see). Does this sound possible/likely? I know thermistors don't tend to fail that often but does it sound possible? What else might it be, if not?
I know it's a simple enough job to test a thermistor with a multimeter but I have not opened the boiler case or looked inside, and will not be doing so. I want hot water but not enough to do illegal gas work or put myself, my gf or our neighbours in danger of CO leaks or anything like that. What I want is to be able to put this possibility to the plumber the next time he (inevitably) comes around and not feel like a plum for doing so. I would do this diplomatically of course; I don't want to seem like I'm teaching my grandmother to suck eggs!
Finally, I know the real solution is "chuck out that pile of crap and get a decent boiler", but as mentioned, we're tenants. And have you ever tried to convince a landlord to spend the thick end of a thousand quid on installing a new boiler when the old one could limp on a bit longer?
Thank you everyone!
