aps faulty

[londongas]

evening. can a faulty APS cause a combi to overheat? read in a combi fault finding book and cant understand how a aps can cause this??

 

[gavinda]

if it stuck in the on postion on certain boilers it could allow the boiler to fire without the pump running . never ever had it happen mind you.

 

[londongas]

thanks.what models should i look out for ?

 

[namsag]

A faulty air pressure switch alone would not cause a boiler to overheat .
Pcb does a check first to make sure the air pressure switch is not already made from previous on period if the boiler then came on it would mean the board was faulty.

 

[LUNAT]

HI

never came across a boiler where APS caused the boiler to overheat.

 

[bengasman]

aps can not make boiler overheat as it is neither related to gas use, nor to waterflow

 

[Agile]

I have seen an early Vokera which did not check the APS.

A bodger had reconnected the APS so that the flame would come on without the fan needing to be on.

As there was no new air coming in the results were far less dramatic than you might expect!

However, it could potentially burn the gas off at the outside of the flue which would have been rather odd to look at!

Tony