Biasi Combination boiler problem

leightravelclub · 27 Feb 2009

When turned on, the main burner ignites for around 15 seconds, then goes out. It will not re-ignite unless the boiler is switched off then turned on again. Then the burner wil light for around 15 seconds again and then go out. After around 15 minutes trying to get it to light and repeating this cycle, the radiators begin to heat up. Can anyone one help with a cure?
Thanks

pipshady · 27 Feb 2009

could be to do with flame rectification or the flame sensing electrode, or even a thermistor fault, what biasi boiler is it?

Agile · 27 Feb 2009

After you have given the model number can you time exactly this "around 15 seconds"

Measure it several times and see if its always the same time.

When this happens do you get any fault light indiscations?

Tony

leightravelclub · 27 Feb 2009

Thank you for speedy responses.
The model number is 24S
The exact time the burner stays alight is ten seconds and it is always the same.

One other odd thing.......once the burner has gone out, if I turn on a hot water tap then turn it off again, the burner will once again ignite though it doesn't produce hot water from the tap. But, if I do this often enough, then the rads heat up!!!!

shambolic · 27 Feb 2009

Check the supply and make sure the neutral is ok too as it defo sounds like no rectification. If all ok and Detection probes and leads ok and gas pressures ok then probably your ignition pcb. (depending on model Ideal Mini the same)

Agile · 27 Feb 2009

I he has given the correct model number its nothing like an Ideal Mini!

The 10 secs is a little odd as it does not point to anything in particular.

It could be a faulty ignition PCB or something else that I cannot mention except to a CORGI.

At the boiler I would identify it within three minutes but from the description given its not obviously any one cause.

The diverter valve may also be faulty.

Tony

Tony

clf-gas · 27 Feb 2009

leightravelclub said:
One other odd thing.......once the burner has gone out, if I turn on a hot water tap then turn it off again, the burner will once again ignite though it doesn't produce hot water from the tap. But, if I do this often enough, then the rads heat up!!!!

I would definately go with the DV, but like you Tony Iam confused as to only 10 sec's. Very quick for the stat to kick in, unless on low temp setting.

I would say without being there to diagnose, DV motor failed and not moving valve, though would of expected to be open to heating

Agile · 27 Feb 2009

This is a Prisma 24S.

No diverter valve motor!

Its the diaphragm diverter if he has told us the correct model!

Tony

clf-gas · 27 Feb 2009

Agile said:
This is a Prisma 24S.

No diverter valve motor!

Its the diaphragm diverter if he has told us the correct model!

Tony

Yeah true Im thinking Riva compact, We would be better with the M90..(letter) model number

leightravelclub · 1 Mar 2009

Thanks again for all advice. I have found the service manual on line and am working through it. Here is a link to that manual which should clear up any confusion about which boiler it is. Thanks again.

http://www.biasi.co.uk/pdf/S RANGE/SERVICE/S1199 EDITION.pdf

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Biasi Combination boiler problem

pipshady

Similar threads