DIY Doctor

boiler issues

Postby neill ward » Mon Apr 28, 2008 12:32 pm

hi everyone

i have an ideal isar HE 30 boiler, when i turn the thermastat down on the living room wall to frost stat, then try to turn it up again the boiler does not fire up, the same happens with the hot water (combi boiler)
i have to go into the shed the status is flashig F then L when i press the reset the number 5 appears then C then D.then it is ok until i turn the stat down again. any help gladly appriciated
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Simply Build It

Postby htg engineer » Tue Apr 29, 2008 4:31 pm

If you left the room thermostat alone would the boiler work day after day without going to lockout ?


Codes L - F means that the boiler has attempted to light 3 times and failed. So it could be a problem with the PCB, igniton, flame sensing electrode/lead or gas valve. With the fault being linked to the room stat I would imagine the fault would be with the PCB.

It'll probably be best to get an engineer out to take a look.

How old is the boiler ? out of warranty ?
htg engineer
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