My 28i Junior delivers hot water fine. It switches off and back on at intervals, but only for a few seconds, so not enough for the water temp to change significantly.
The CH is very erratic. Sometimes it runs OK, but most often the fan switches itself off a second or two after ignition and shortly after that the thing shuts down with the fast flashing error light. About 50% of the time, if I run a hot tap for a while, switch the CH on and then turn the tap off the CH will manage to start itself OK, i.e. the fan comes/stays on. It might then run for sometime, but once the radiators have heated up enough and it switches itself off again, the same problem can occur. I might get half an hour of heating or I might only get a few minutes!
For info, the CH loses pressure, and when it's low (below about 2 bar) it's even less likely to start. I normally run the CH with the radiator temperature set high, but when I set it to its minimum setting it ran for a long time without losing much pressure. The trouble is that on low the thermostat switches it off sooner and more often, so it has more opportunities for the fan failure to occur.
The boiler predates my living at this address, so is more than 15 years old. In the time I've been here it's had a replacement air pressure switch in the flue, and in 2013 a replacement relay on the control board. At that time HW would run in the low burn setting, but wouldn't go to high burn. I could get a trickle of hot water out but if I turned on a tap beyond that it would cut out. Replacing the relay fixed the problem. It was late Sept / early Oct, so I don't think I'd tried the CH at the time. I presume that the CH, requiring high burn, would have failed.
Does this sound like a faulty relay again? Last time it simply didn't work at all on high burn, but this fault is intermittent, and the HW is mostly OK. Maybe it's on the way out...
Any other ideas?
Thanks.
The CH is very erratic. Sometimes it runs OK, but most often the fan switches itself off a second or two after ignition and shortly after that the thing shuts down with the fast flashing error light. About 50% of the time, if I run a hot tap for a while, switch the CH on and then turn the tap off the CH will manage to start itself OK, i.e. the fan comes/stays on. It might then run for sometime, but once the radiators have heated up enough and it switches itself off again, the same problem can occur. I might get half an hour of heating or I might only get a few minutes!
For info, the CH loses pressure, and when it's low (below about 2 bar) it's even less likely to start. I normally run the CH with the radiator temperature set high, but when I set it to its minimum setting it ran for a long time without losing much pressure. The trouble is that on low the thermostat switches it off sooner and more often, so it has more opportunities for the fan failure to occur.
The boiler predates my living at this address, so is more than 15 years old. In the time I've been here it's had a replacement air pressure switch in the flue, and in 2013 a replacement relay on the control board. At that time HW would run in the low burn setting, but wouldn't go to high burn. I could get a trickle of hot water out but if I turned on a tap beyond that it would cut out. Replacing the relay fixed the problem. It was late Sept / early Oct, so I don't think I'd tried the CH at the time. I presume that the CH, requiring high burn, would have failed.
Does this sound like a faulty relay again? Last time it simply didn't work at all on high burn, but this fault is intermittent, and the HW is mostly OK. Maybe it's on the way out...
Any other ideas?
Thanks.
