Gas Boiler not firing up

[Staypuft]

Hiya, just after some advice really..

I have a Main Medway Super gas boiler which has been working fine untill the past week..

Now it takes a tap to be on full to get it to fire and if you let the pressure off a little it stops...

Am I right in thinking this is something to do with the Diaphragm? I like to have some idea of the problem when the engineer calls.

 

[gaspro1981]

It's a possibility

 

[Agile]

We call these instant water heaters!

Tony

 

[Homesafe]

you're on the right track.

 

[gas112]

Agile we actually call them instantaneous multipoint water heaters

Yes its a stretched diaphragm but although this is water section do not attempt a repair yourself as the pin it operates goes into the gas section and the slightest bend in it can cause htr to stay on and go bang with water everywhere.
So get someone who actually knows how a multipoint comes apart unfortunately that rules out a lot of newcomers over the past ten or more years into the trade

 

[Agile]

I was wondering about the need for an RGI but could not think of any over riding reason to insist on an RGI.

If I had said that then several would have told me there is no legal requirement for an RGI

 

[gas112]

Same pin that scales up and keeps htr on when tap turned off with resulting bang and hot outlet blowing off