I have an Ariston Eurocombi (A23).
The problem is it doesn't realise the flame is lit. When I start it up and cause demand (run hot tap or turn on heating) it fires up the flame correctly, however, you can hear the igniter still clicking away. After about 7 seconds of this (flame working correctly, but igniter clicking) the boiler then shuts itself down and lights up the "Ignition failure" light. I can press the reset button but the same thing just happens again.
I don't think the problem is related to over-heating because if I leave it alone for a few hours, then try running hot water again, the problem is still there. However, If I turn it off, and off at the wall, then wait for at least an hour or so, I can get it to work again for about 1/2 an hour.
I assume the problem is either with whatever detects the flame is lit, or the board that responds to that sensor.
Any suggestions for how to diagnose (or better still, fix) the problem?
Thanks,
Matt
Best Answer
I believe it is fairly normal for the igniter to continue to fire for several seconds after ignition, I guess this is because it takes a while for the flame sensor to heat up - and probably also for performance/safety reasons.
Boilers have a flame-sensor, it sounds like your has failed. You can buy replacements.
I think this is a job most people leave to a boiler service technician, you need special tools (e.g. multimeter with microamp range) to check those sensors.
Gas appliance repair is safety critical, probably best left to those with training and experience.
19 = "detection electrode" 20 = ignition electrodes. See manual
A07 = flame detector. A09 = flame detection circuit. A10 = flame indicator LED - I'd check this is "on" after 5 seconds of successful ignition.
Don't rule out other causes, boilers shut themselves down for lots of reasons, maybe the flue is iced up or the water pump isn't operating.
The manual contains a troubleshooting flowchart and a parts list that includes the flame sensor.