Biasi 24S Problem

28 Nov 2010
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United Kingdom
Hoping someone may be able to help with this problem.
Our Biasi 24s combi boiler was working fine until a few days ago. Now, the hot water is heating up as usual, but the pilot light for the central heating only remains on until the temperature gauge hits 75-80 degrees, then the pilot light goes out, and won't restart until the temp gauge drops. Never had the problem before.
Coincidentally, we had an old gas fire disconnected and removed the day before we started having probs with the boiler. Could the problem be related to a change in the mains gas pressure since the plumber disconnected the old gas fire? (He claims not)
Would appreciate any assistance.

Many thanks
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best to get someone in to look as it could be a couple of things,and it would be a bit of a guess on the forum, but the plumber wont have affected the gas pressure by removing the fire. so probably coincide4nce

Apart from measuring the sensor resistance I dont see there is going to be much that you can do apart from calling a pro.

What happens whe you turn down the heating control knob?

Thanks for your quick responses.
When the temp control knob was turned down a bit, the pilot light still went out, this time at around 68 degrees.

Any other thoughts/suggestions?

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Reading what you have said, I am now thinking that your boiler is probably working correctly.

Once the boiler reaches the set flow temperature, if it cannot modulate further down then it goes out for the duration of the anti cycle delay of about three minutes.

All that MIGHT be wrong is that the gas valve is not set up correctly. You MAY need someone to service it but that must be someone who knows how to set the minimum and maximum burner pressures not that many people do know.

Tony Glazier

DIYnot Local

Staff member

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