I'm from Australia where we don't have central heating, so I'm new to how these systems work. I've done a fair bit of reading, unfortunately none of which has helped me understand the symptoms my boiler is showing.
I filmed a short video of it "running": https://youtu.be/U11Yh4R7PNY
In the video you can see and hear (turn the sound up) that the main burner ignites, stays running for a few seconds, then extinguishes. A few seconds later the ignition is activated again and the boiler relights, only for the cycle to continue. This doesn't fit with what I would expect to happen if there was a problem detecting ignition, or if a thermostat/thermocouple was reading incorrectly. The cycle begins immediately there is demand, even from cold.
The same cycle occurs with either DHW or CH demand, and the pump and fan can be heard operating also.
I don't intend to fix this myself, but there doesn't seem to be many boiler service people in my area (South Northants) that advertise their familiarity with Sime boilers: the first person we had investigate watched it cycle, checked the gas pressure (fine) and shrugged his shoulders.
Any suggestions on what the cause may be are welcome!
I filmed a short video of it "running": https://youtu.be/U11Yh4R7PNY
In the video you can see and hear (turn the sound up) that the main burner ignites, stays running for a few seconds, then extinguishes. A few seconds later the ignition is activated again and the boiler relights, only for the cycle to continue. This doesn't fit with what I would expect to happen if there was a problem detecting ignition, or if a thermostat/thermocouple was reading incorrectly. The cycle begins immediately there is demand, even from cold.
The same cycle occurs with either DHW or CH demand, and the pump and fan can be heard operating also.
I don't intend to fix this myself, but there doesn't seem to be many boiler service people in my area (South Northants) that advertise their familiarity with Sime boilers: the first person we had investigate watched it cycle, checked the gas pressure (fine) and shrugged his shoulders.
Any suggestions on what the cause may be are welcome!