Earlier last month (April) my heating was still on ( i run it on low flow temp of between 35° - 40 C continuously) we still had a fair amount of chill during April. So one April day it went off, causing me to get a gas safe mate to look at the boiler just in case. He could find nothing obvious, and carried out a full flue analyser test, and all readings showed normal and well below thresholds.
Luckily, my gas safe mate did not charge me anything, all seems fine, yet we could not find out why the detector went off unless it is going potty, it is (the detector) about 4 years old into service.
Then I happen to have a spare CO detector, a different make, so I placed it on the wall next to the one that went off, then last week the older one went off again, the spare one showed less than 1 ppm, the one that went off showed in excess of 500ppm!
So I reset the detector, and hoped for the best, today it went off again, showing excess of 838ppm, needless to say the detector seems terribly unreliable, as the other one still showed less than 1ppm, and the boiler had been off now for almost two weeks. No one was using any hot water at the time, or doing any cooking, after i cleared the reading, I took it down, and puffed lungs full of smoke into it, within a minute it went off indicating over 200ppm, then in another minute or two it self reset when the smoke disperses and the reading goes down to less than 100ppm. (Cigarette smoke contains a fair amount of CO in one puff!)
I then did the same to the new spare detector, just to make sure it goes off, A puff of smoke from a cigarette in the spare showed a reading of 51ppm and it did not go off, and the reading went back down to less than 1 ppm, in under a minute.
Perhaps it may be a good idea to throw away an old CO detector that goes off for no apparent reason, and no faults could be found with your boiler or its flue components. In the long term it would be cheaper to replace an unreliable CO detector rather than having to keep on calling an engineer and pay him for an unnecessary (FALSE ALARM) call out charge when there could be nothing wrong with your boiler or its flue.
I can't imagine how some dubious engineer who may actually condemn your perfectly OK appliance, and seal it off as immediate danger, and you are talked into getting your old boiler replaced at a fortune.
Better still, get two CO detectors, as you cannot rely on one alone, that would work out a lot cheaper than a charge for a single call out. If there was genuine CO presence , both detectors would show a high reading, that is when you must call an Engineer to check your appliance.
If in any doubt, turn your boiler off and call an engineer for safety.
Luckily, my gas safe mate did not charge me anything, all seems fine, yet we could not find out why the detector went off unless it is going potty, it is (the detector) about 4 years old into service.
Then I happen to have a spare CO detector, a different make, so I placed it on the wall next to the one that went off, then last week the older one went off again, the spare one showed less than 1 ppm, the one that went off showed in excess of 500ppm!
So I reset the detector, and hoped for the best, today it went off again, showing excess of 838ppm, needless to say the detector seems terribly unreliable, as the other one still showed less than 1ppm, and the boiler had been off now for almost two weeks. No one was using any hot water at the time, or doing any cooking, after i cleared the reading, I took it down, and puffed lungs full of smoke into it, within a minute it went off indicating over 200ppm, then in another minute or two it self reset when the smoke disperses and the reading goes down to less than 100ppm. (Cigarette smoke contains a fair amount of CO in one puff!)
I then did the same to the new spare detector, just to make sure it goes off, A puff of smoke from a cigarette in the spare showed a reading of 51ppm and it did not go off, and the reading went back down to less than 1 ppm, in under a minute.
Perhaps it may be a good idea to throw away an old CO detector that goes off for no apparent reason, and no faults could be found with your boiler or its flue components. In the long term it would be cheaper to replace an unreliable CO detector rather than having to keep on calling an engineer and pay him for an unnecessary (FALSE ALARM) call out charge when there could be nothing wrong with your boiler or its flue.
I can't imagine how some dubious engineer who may actually condemn your perfectly OK appliance, and seal it off as immediate danger, and you are talked into getting your old boiler replaced at a fortune.
Better still, get two CO detectors, as you cannot rely on one alone, that would work out a lot cheaper than a charge for a single call out. If there was genuine CO presence , both detectors would show a high reading, that is when you must call an Engineer to check your appliance.
If in any doubt, turn your boiler off and call an engineer for safety.
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