Baxi solo3 60 PF shutting down/restarting

[LenS]

Problem started with fan seizing. Corgi man replaced fan enabled boiler to start but after 3-4 minutes it shut down then immediately restarted (have read other posts on this subject). It continued to do that. Replaced PCB, no improvement - worse wouldn't even keep running on room stat. replaced gas valve and solenoid - no better, reset fan gasket with silicon sealant - no better, dismantled and cleaned pilot and main burners - no better, replaced air pressure switch and tubes - no better. Re-installed original PCB, does at least keep running on room stat. Replaced thermostat and overheat thermostat - no improvement. Exchanged first new PCB as faulty, installed the replacement no different from original PCB.
My CORGI engineer has many years of experience and I am a professional engineer, FIMechE and we are both baffled.

 

[Aquaheat]

I'm gonna guess that he has got the wrong fan as there are two types for this model, if he has the fan for the larger boilers it could be lifting the flame/gas and not allowing itself to rectify.

You say this problem only popped up after fan change so stands a very high chance. Check part numbers but also check that its the right fan in the box.

I will try and source P/N for correct fan

 

[Aquaheat]

message removed

 

[gas4you]

The pfl60 has the larger fan

 

[LenS]

I'm not totally sure it wasn't doing it before the fan seized, only became aware of it after replacing fan and watching it fire up

 

[Aquaheat]

thats why i removed my second post Dave, wasn't 100% sure on the exact one for these, I had a picture of a solo 2 in my head when doing the first post

 

[gas4you]

Try removing the flue/fan restrictor.

 

[LenS]

jonjb, I didn't see your second post. Are you saying we might not have the wrong fan? My manual says the mfr's P/N is 246052 for 60,70 & 80. Can't check it at moment as corgi man not available, and box and seized fan went with rubbish on Tuesday.
Surely gas4you suggestion of removing restrictor will be the equivalent of putting in a bigger fan as opposed to already having a too big fan.
Thank you for all suggestions

 

[baxpoti]

Type of flue
Horizontal or vertical
Length etc

 

[LenS]

38 cm from restrictor plate to end of flue, horizontal but very slightly down towards the outside.

 

[baxpoti]

A 'new' pressure switch for the 60, has a part number 5111609 (yellow label) replacing Part number 246054.

Which one has been fitted to yours?

On the restrictor is it stamped 60?

 

[LenS]

Thanks baxpoti will let you know Monday when Corgi man comes again with paperwork

 

[gas4you]

Baxpoti will know for sure, but I had, a few years back, 3 of these that had the flue restrictor the wrong size, even though they were stamped 60.

I was told that there was a batch that were produced wrong, but I've got no firm proof.

Over to you Baxpoti

 

[LenS]

Do you know what bore the correct 60 restrictor should be?

 

[LenS]

Finally working OK using gas4you suggestion of removing restrictor plate. Baxi also suggested that to my corgi man this morning - do they read this forum?
As matter of interest plate was stamped 40/60 seeing that would cover two different sizes of fan is a bit strange. Actual bore was 35mm
Thanks to everyone who made suggestions