Baxi 105

[lukeuk]

Hello everyone,

Just replaced a corroded diverter valve and everything works fine apart from hot water is cutting out and starting up repeatedly while running. Ive felt the pipes going into the heat ex and they are getting red hot so imagine this is possibly somthing to do with it over heating?

Another problem i found on the boiler is that the burner pressure was real low, like 2mbar, when i put it up to 12 the closest i could get to 13.5 it would make a loud whooshing sound in combustion chamber then obviously continue to cut out when running it in hot.

Central heating appears to be working fine.. i have tried installing a new plate heat ex but same problems persist.

 

[45yearsagasman]

Are you a trained and registered gas engineer?

 

[lukeuk]

yes im time served, finished 4 year plumbing apprenticeship last year.. finished gas last june.

 

[MUFC1999]

yes im time served, finished 4 year plumbing apprenticeship last year.. finished gas last june.

No specific central heating/ boiler training then?

 

[namsag]

Hope you realise it IS meant to light at 2mbar before going to 13.

Valve has a hi and low gas setting.

If everything IS ok then it sounds like plate is blocked and needs cleaning or changing

 

[lukeuk]

nah it sticks at 2, i tried replacing plate but same problem.

 

[namsag]

OOPS neva noticed you had tried plate.

Sensor just by the plate could be duff

 

[lukeuk]

thanks for replies namsag, im sure it a prob with with overheating because the pipes are getting seriously hot, also the hot water stat does not appear to heat in any way.

 

[Blackadder43]

I have to ask this which is probaly going to turn out to be a stupid question, but how on earth did the Gas pressure manage to get itself all the way down to 2mb?
And how on earth has this boiler worked like this?

Instead of re-adjusting said gas pressure i am more inclined to think something is wrong somewhere?

Also you say diverter was well corroded, is it possible that some of the corrossion has now made it to the plates?

 

[lukeuk]

this is what i am thinking, the tenant mentioned that the council had carried out some water works and this caused her sisters boiler up the road to become damaged etc.. so i think whatever has caused diverter issues may have blocked up pipe work or damaged heat-ex.