24i Junior problem(SE)

[GQuigley67]

got a problem with this boiler, nothing is operating whatsoever and its flashin red around once per minute.

I'm the 3rd guy to have a look at it, its for my auntie's tenant. First guy changed gas valve, 2nd guy changed PCB still the same.

I have tested the water pressure switch with my multimeter and I'm getting continuity, took it out and cleaned all the sludge from it, checked the overheat stat also fine, I am getting 240v to the PCB but no power to the pump.

No continuity at APS, not sure if that's what i should be getting or not been a while since I've attempted any repairs.

To me it sounds like the PCB isn't sending signal to pump, but the PCB is brand new so I'm stuck

 

[GrahamM]

This is a tough one.
Was a few years ago but I had a dodgy transformer on one of these.
You can check resistance across the pins IIRC was about 80ohms.
Cant think anything else if board is new although have had new boards that are faulty.

 

[gassafe]

A call to Worcester might be the best & cheapest option, there normally pretty good.

 

[GQuigley67]

The fan ans pump are 240v though so they would be takin off before the transformer would they not

 

[breakdown]

I would link out water pressure switch and overheat stat. I have checked for continuity before all fine but did not fire up. Linked them out and it fired up. It was the water pressure sensor.

 

[anz]

When you reset it, does it spark for a few seconds before locking out?

 

[GQuigley67]

When u say linked them out do you mean disconnect it? It doesnt spark there is no power goin to pump isnt the pump the first thing in the sequence of operation

 

[GQuigley67]

also the pump is 240v so i couldnt see the transformer being the issue, I'll go back down tonight have a look at it maybe phone worcester

 

[GQuigley67]

Problem solved, was on the phone to worcester while at the boiler and he said if if its not transformer its PCB, tested transformer and then thought it was PCB, when putting transformer back on I heard a rattling noise, turns out the plastic reset button had snapped off the part of the casing which held it in place so when you were pressing the reset button it wasnt doing anything. Put it all back together and used my long philips driver to press the reset button on the PCB and boiler fired up.

Luckily I spotted it by pure luck or it would of been a new PCB as I dont think they would have accepted that one as a return as it was 3 weeks old!

 

[mountainman]

Well spotted:thumbup: