Boiler knocking - no heat

[Nightsky]

I have a Thorne Apollo gas boiler which is situated in the roof space. The boiler started banging last Thursday when it came on. I had previously turned down the thermostats on three of the radiators but this banging did not start until several days after I had done this. I have bled all the radiators and the topmost bleed valve in the loft; the only radiator with air was the one in the bathroom and very little air came out.

I phoned my gas engineer on Friday when it was clear I was not competent to deal with the problem and with whom I have had annual servicing contracts for the past 35 years. He was unable to come out until today and now has phoned to say he cannot do it until tomorrow. (The same thing happened two years ago when he left me in the cold for days.)

First can you give me some idea why my boiler is having a hissy fit and should I be having one with my engineer?

 

[kevplumb]

do you have trvs on all the rads ?

 

[Nightsky]

Yes - no room thermostat.

 

[kevplumb]

if the trvs are all closing the water in the boiler cant go anywhere and is boiling try opening one full

 

[Nightsky]

All the thermostats are full on but problem persists.

 

[kevplumb]

do you have a bypass fitted

check the pump ?
diverter valve ?

water in the head tank ?

 

[Nightsky]

Kev - this is too advanced for me, hence my need for a reliable Corgi man!

However, should you need a nice steak and kidney pie - no problem.

I can confirm water in header tank.

 

[Nightsky]

Today engineer sorted problem out of banging boiler. Having fitted a new pump there was still something wrong. They were unhappy with the wiring for the pump and decided that there was no need for a piece of wiring and disconnected it. Everything now working OK. The fee for this work was £190. I feel fleeced - should I?

 

[ChrisR]

Depends what the piece of wire was doing...