Okay, I've had this problem for years and never really got anyone to fix it.
First up, the boiler: Industrie Fer Hawk II, combination boiler (instructions are on their web site for download, as that's where I got them). Boiler is some 10 to 15 years old I think. It was there when I bought the house back in 1999.
Basic problem is that when the days get colder, the boiler will more frequently light for a few seconds or a minute and then just cut out. I have to increase the boilerstat to max the colder it gets just to try and get it to come on at all.
Sometimes I can hear a relay or something clicking on and off rapidly as it appears to try and decide whether to turn on.
I'm under a contract with British Gas that despite a number of call outs, has not really resolved it. I'm sure their final solution would be to replace the boiler, but there's nothing actually wrong with the heating side of the boiler, just the bit that's instructing it to light up.
Anyway, so far they've replaced the circuit board, air pressure switch, some sort of thermostat (going by the instructions I've got and what I saw the guy replace, I think it may have been the overheat cut-off thermostat), the heating boilerstat.
On the last visit they suggested getting a room thermostat, as I didn't have one. So I've fitted one, and that works fine when the heating is working. When it's not the thermostat is just correctly calling for heat as the room is too cold. The boiler however never provides enough heat. When it's very cold (like now), the radiators can just be stone cold.
When it's warmer however, the boiler behaves itself and the radiators can get nice and piping hot and the room thermostat kicks in at the right temperature to shut the system down, and back on again when the temperature drops. The problem is always when it is much colder outside.
One thought I have is the Central Heating Flow Temperature Sensor. One of the guys who came out once mumbled something about that but never replaced it.
Curious about this, I took the connection off this sensor and connected it to the hot water sensor instead, and sure enough the boiler fires up and behaves fine (obviously I don't get hot water unless I restore the connections).
Probably a very dodgy "hack", but I get a warm house. Note that once I've got the house warm, I can restore the connections and the boiler will behave itself again for quite a while, until the boiler goes off on the timer and cools down, then it will struggle to fire up again next day.
Opinions? Could it be the CH flow temp sensor, and if so, how easy is it to replace? Any other suggestions for what it could be?
Oh, and could it also be (still) the boilerstat (the knob on the front panel)? This had been replaced before, but it's still got a strange behaviour where just a very gentle touch without turning it can cause the boiler to cut out.
I don't really just want to call BG out for them to tinker and scratch their heads again and not fix anything (and it costs me money to take time off work). Also it's one of those typical things that doesn't go wrong when you call them out (though being cold right now it might do).
I have a picture I've uploaded also showing the sensor connections.
First up, the boiler: Industrie Fer Hawk II, combination boiler (instructions are on their web site for download, as that's where I got them). Boiler is some 10 to 15 years old I think. It was there when I bought the house back in 1999.
Basic problem is that when the days get colder, the boiler will more frequently light for a few seconds or a minute and then just cut out. I have to increase the boilerstat to max the colder it gets just to try and get it to come on at all.
Sometimes I can hear a relay or something clicking on and off rapidly as it appears to try and decide whether to turn on.
I'm under a contract with British Gas that despite a number of call outs, has not really resolved it. I'm sure their final solution would be to replace the boiler, but there's nothing actually wrong with the heating side of the boiler, just the bit that's instructing it to light up.
Anyway, so far they've replaced the circuit board, air pressure switch, some sort of thermostat (going by the instructions I've got and what I saw the guy replace, I think it may have been the overheat cut-off thermostat), the heating boilerstat.
On the last visit they suggested getting a room thermostat, as I didn't have one. So I've fitted one, and that works fine when the heating is working. When it's not the thermostat is just correctly calling for heat as the room is too cold. The boiler however never provides enough heat. When it's very cold (like now), the radiators can just be stone cold.
When it's warmer however, the boiler behaves itself and the radiators can get nice and piping hot and the room thermostat kicks in at the right temperature to shut the system down, and back on again when the temperature drops. The problem is always when it is much colder outside.
One thought I have is the Central Heating Flow Temperature Sensor. One of the guys who came out once mumbled something about that but never replaced it.
Curious about this, I took the connection off this sensor and connected it to the hot water sensor instead, and sure enough the boiler fires up and behaves fine (obviously I don't get hot water unless I restore the connections).
Probably a very dodgy "hack", but I get a warm house. Note that once I've got the house warm, I can restore the connections and the boiler will behave itself again for quite a while, until the boiler goes off on the timer and cools down, then it will struggle to fire up again next day.
Opinions? Could it be the CH flow temp sensor, and if so, how easy is it to replace? Any other suggestions for what it could be?
Oh, and could it also be (still) the boilerstat (the knob on the front panel)? This had been replaced before, but it's still got a strange behaviour where just a very gentle touch without turning it can cause the boiler to cut out.
I don't really just want to call BG out for them to tinker and scratch their heads again and not fix anything (and it costs me money to take time off work). Also it's one of those typical things that doesn't go wrong when you call them out (though being cold right now it might do).
I have a picture I've uploaded also showing the sensor connections.
