Back Boiler pilot light goes out when the fire is turned on

[clairec]

Hi - we have a Myson Back Boiler with a Baxi (?) gas fire attached - whenever the fire is used, the boiler's pilot light goes out and has to be relit manually using the spark button.

The first time we noticed this problem (a few days ago), we heard a loud noise that came from somewhere behind the fire when it had been on for an hour or so, so I wondered if something has expanded in the heat and broken/ moved out of place a bit?

The pilot light looks fairly blue and healthy when it is lit and the boiler/fire was stripped down and serviced in April. We have no problems with the boiler lighting, other than when the fire is turned on! Does anyone have any ideas?

 

[Slugbabydotcom]

Not familiar with the particular model but it does sound to me like there could be an oxygen depletion sensor [ODS] also known as ASD on your boiler which is cutting out the pilot.
Is there adequate and proper ventilation to the room where the back boiler is fitted?
Are there any obvious problems with the flue?

 

[chrishutt]

It could be that your gas supply pipework is inadequate for the gas flow required and that therefore the pressure drops when the gas fire is turned on, causing the pilot flame to reduce in size just enough to fail to maintain the temp. of the thermocouple.

You need a Registered Gas Installer to check the gas pressures to determine if this is the cause. Slightly increasing the flow to the pilot light or replacing the thermocouple might deal with the symptoms, but the underlying problem needs addressing.

 

[ChrisR]

Now could it just be dirt in the pilot .....have we been here!

COuld be several things. I did a Landlords Cert on a back boiler/fire, and the landlord decided it would be a good idea to build plaster up between the hearth and the case of the fire all round the bottom, a couple of days later. So the boiler could only get its air through the fire. The boiler worked for a year like that. Luckily nobody tried to use the fire.

 

[DP]

Check meter control is fully open!!

 

[gstens baxi]

I would seriously call a corgi engineer as mixing the make of fire and back boiler is not normal/safe.The pilot outage could also be put down to a spillage of fumes from the fire.GET IT CHECKED.