Stymied!!! Raybuen XT gpf

[lame plumber]

right clever clogs, I have a Rayburn XT gas, with power flue, no longer in production thank god. It is the bane of my life and the customers, last year it need a new power flue fan, controls pcb amongst other things.

This year it is knackered again. The burner unit is similar to an oil burner unit in that it has its own honey well pcb controller linked to the main pcb .

the issue, the fan starts, spark unit clicks away and it fires up, burns for a few seconds, max of 12 secs and cuts out, fan stays on and fires up again and off repeatedly. So muggins went for the new ionization probes and lead, plus control box to cover the old arse as I had cleaned the old probes and all looked ok, plus AGA tech advised the same. £150 later!!!!!!! same issue and AGA tech now says change the fan as the built in APS is probably sticking or the fan speed is too low or they dont know.....................

Any thoughts, just ripping handfuls of hair out today..

 

[Nostrum]

Have you checked the earth for good continuity? I wouldn't have thought the Burner would light if APS wasn't making, unless it is dropping out constantly, you could check by checking for continuity through the switch itself.

It sounds more like it's not recifying as you thought but the probe isn't the cause.

I take it flame isn't lifting off the burner and all visuals OK?

 

[lame plumber]

no flame lift,checked for rectification an got about 6ma (3-7 wanted), earths fine, new probes, leads got continuity, aga say aps is built into gas valve (burnertech burner, honeywell contoller and gas valve) not sure how but the air intake hose feeds back to the gas valve, but no movement felt on sucking hoses so can only suspect a jammed switch or failing fan. nightmare