Ravenheat littlestar boiler

[richardlewis1964]

Hi All
I will descibe best I can

Its been working ok till today
Pressure in boiler is constant 1 bar when cold
No hot water ? went and had a look and its sitting at 1 bar , turn on hot tap and all seem normal and boiler lights, within 20 secs pressure jumps up all over the place and boiler shuts down. lots of hissing and banging etc.
Normally hot water only and the pressure guage dont move.
does the same with central heating pressure jumps about then shuts down and trip swith trips

help !!!!!!!!!!!!!!!

 

[adlplumbing]

sounds like blockage in the diveter vavle
get it changed

 

[WarmsureIdealengineer]

Sounds like the Pump to me, if the pump isnt running then the boiler will quickly go to overheat and will do what you have described.

 

[richardlewis1964]

someone said expansion vessel ?? is this used on hot water only ??

 

[richardlewis1964]

is the pump used for hot water only ???

 

[adlplumbing]

pressure mounts up as pump is running water does not move so it boils
and then comes put of the aav last time i saw this and it blockage
in the divter valve

 

[richardlewis1964]

thanks all

It was a dry joint on the PCB that was stopping the pump running !!!!

Removed resoldered and refitted and hey presto saved a fortune


Thanks all