Hi, I am after some pointers to help diagnose an issue with my system boiler (Glow worm 18hxi). It is a system boiler with unvented Ariston 150L hot water tank and 2 expansion vessels (one each for HW and heating). There is a motorised valve (2 way) on each of the Hot water feed and heating Feeds. The boiler had been running OK and had last had a service 14months ago.
Back in May this year I had my incoming gas line and meter moved by SGN to a different location due to some home renovations and also 2 radiators have been capped off (pending re-installation once the works are completed). The heating system was drained to remove the radiators and re-work the feed pipes to a new location. I also had smart meters installed at the end of August.
Since both of those events have happened the boiler has been happily running morning and late evening for hot water on the timer. The heating didn't come on due to the warm weather and the thermostat set below what the air temps were. However, now the colder temps have required the central heating to come on and this is where I am noticing an intermittent fault.
If I change the programme to only provide Hot Water, the boiler works as expected, heats the water, shuts off when at temp and reignites to replenish any used water, same as noticed throughout the summer.
Engage the central heating, and some days it will work fine for a short period of time (40mins as an example) but then shuts off. The radiators are warm/hot to the touch and I'll check the boiler and there will be a red flashing light (error). Other days it doesn't seem to ignite when the programme calls for the heating to come on. Sometimes I get an F1 fault (which according to the manual could be about 6 or 7 things). I've had the PCB board (1st heating engineer said it was likely that causing the issues). hasn't resolved the problem and still not sure why the HW is OK and is only the central heating that causes the issue.
I have since change the programmer to manual mode, so I can control / check what the boiler is doing when on.
I should add - there was a lot of brick dust in the air so could it be related to the room thermostat as that was in the same space?
I did notice that the 2 capped radiators the end of the pipes are cold even when the heating is on, I was expecting at least 1 side to be warm/hot as this would be the feed. Therefore could it be something like an airlock within these moved heating pipes which are capped off causing a pressure fluctuation that the boiler doesn't like ? - I can't exactly bleed these pipes just yet but wondering if I should install the 2 radiators back again to allow for easier bleeding or am I barking up the wrong tree?
Saw this thread also - https://www.diynot.com/diy/threads/...xi-short-cycling-kettling-air-trapped.620591/ - I don't think anything special was done either before or after system drain, but I wasn't watching over them all the time to be able to be sure 100%
Obviously so much has changed it is hard for me to know what to look at first and the reason why I paid for a heating engineer but before I spend any more money on random parts / an engineer (will likely go with a different person next time) is there anything I can check ?
Back in May this year I had my incoming gas line and meter moved by SGN to a different location due to some home renovations and also 2 radiators have been capped off (pending re-installation once the works are completed). The heating system was drained to remove the radiators and re-work the feed pipes to a new location. I also had smart meters installed at the end of August.
Since both of those events have happened the boiler has been happily running morning and late evening for hot water on the timer. The heating didn't come on due to the warm weather and the thermostat set below what the air temps were. However, now the colder temps have required the central heating to come on and this is where I am noticing an intermittent fault.
If I change the programme to only provide Hot Water, the boiler works as expected, heats the water, shuts off when at temp and reignites to replenish any used water, same as noticed throughout the summer.
Engage the central heating, and some days it will work fine for a short period of time (40mins as an example) but then shuts off. The radiators are warm/hot to the touch and I'll check the boiler and there will be a red flashing light (error). Other days it doesn't seem to ignite when the programme calls for the heating to come on. Sometimes I get an F1 fault (which according to the manual could be about 6 or 7 things). I've had the PCB board (1st heating engineer said it was likely that causing the issues). hasn't resolved the problem and still not sure why the HW is OK and is only the central heating that causes the issue.
I have since change the programmer to manual mode, so I can control / check what the boiler is doing when on.
I should add - there was a lot of brick dust in the air so could it be related to the room thermostat as that was in the same space?
I did notice that the 2 capped radiators the end of the pipes are cold even when the heating is on, I was expecting at least 1 side to be warm/hot as this would be the feed. Therefore could it be something like an airlock within these moved heating pipes which are capped off causing a pressure fluctuation that the boiler doesn't like ? - I can't exactly bleed these pipes just yet but wondering if I should install the 2 radiators back again to allow for easier bleeding or am I barking up the wrong tree?
Saw this thread also - https://www.diynot.com/diy/threads/...xi-short-cycling-kettling-air-trapped.620591/ - I don't think anything special was done either before or after system drain, but I wasn't watching over them all the time to be able to be sure 100%
Obviously so much has changed it is hard for me to know what to look at first and the reason why I paid for a heating engineer but before I spend any more money on random parts / an engineer (will likely go with a different person next time) is there anything I can check ?
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