Triancogas WM 25/45 RS - not firing up (with pics)

[bongos]

Wonder if anyone has any ideas for a problem with my boiler...

Switched on the heating this morning and noticed after about half an hour that the radiators were still cold. Went and looked at the boiler and it didn't appear to have fired.

The pump is working as I can hear/feel the water going round but for some reason the boiler wont light. I tried the same with the hot water circuit (which is usually switched off anyway) and same problem. The water was circulating but the boiler was not lighting up.

The pilot is still lit and I've checked the hob in the kitchen to make sure I don't have a disrupted gas supply but its working fine. Any ideas anyone?

Thanks

 

[bongos]

I've added some pics with the front cover off the boiler.

 

[LUNAT]

HI


1.room stat calling for heat ?
2.programmer on ?
3.put the grey control knob on full
4.if all above fails gently tap the grey plastic box
5.loose wires ?check all accessible wires

 

[bongos]

Hi LUNAT. Thanks for your help.

In reply to your suggestions:

1. Room stat is calling for heat. When I switch it below temp it turns off and when I switch it back up the water starts circulating again (albeit the boiler still doesn't fire.
2. Programmer is on.
3. Tried with the grey knob on full. Normally when its on it clicks if you turn the temp of the boiler up when its lit but today it does nothing (prob because its not lit!)
4. Tried tapping the little grey box on the front. Nothing.
5. Checked as many wires as I can. After looking in that FCU (which I knew would be a mess) all I could find was the main earth from the supply disconnected (meaning that nothing on the load side was earthed!). I've reconnected this but still nothing.

Is a possible cause that a fuse may have blown on the PCB? I think this boiler is getting on in age now so I'm not too sure what level of internal circuitry it actually has. Is the PCB fuse an easy fuse to locate and change on this model?

I almost get the impression that the boiler just isn't letting gas into the chamber but I don't know how I can check this!

 

[bongos]

Anyone?

 

[gremlin16]

Nice wiring centre

 

[AlanE]

So have you checked anything to find out just how far the power is reaching within the boiler?

Without this information all that can be given is a list of components that might be at fault and looking at the manual for this boiler that list would include, since it is such a basic boiler, virtually every component that controls the mains supply.

Do some checks and post back. The pictures are great but do nothing to help diagnose the problem.

I presume this boiler is the one with GC No. 41 898 29. Incidently manual is dated 1984 so this will give approx age of the boiler.

 

[Agile]

I dont see any PCB on your very basic boiler!

It modulates by a liquid phial acting directly on the gas valve like the very similar Servowarm boilers.

The position of the gas valve grey knob is critical. Could this have been disturbed?

Tony

 

[LUNAT]

HI

the wiring ?????????feel dizzy

 

[bongos]

HI

the wiring ?????????feel dizzy

Hmmm. It seems the wiring is to blame. I don't have 240v at the boiler so somewhere in all that mess something is wrong. Just trying to work out what!

EDIT: Whoops! Forget that I do have 240V at the boiler (i had the thermostat turned down when I first tested it)

 

[doitall]

Open the port valves manually and see what happens

 

[bongos]

Thanks for your continued help. AlanE FYI I have 240v right upto here...

Open the port valves manually and see what happens

Sorry not sure how to do this? There are two thin switches on top but they don't seem to do anything when I switch them. I have a 2 x 2 port valve system. Is a knackered valve a possible cause?

 

[tonybhoy]

If your getting power at the gas valve and the pilot is still lit then the valve is faulty.

You'll have a job getting hold of one of those valves which is just a basic Honeywell gray button valve with a modification made for Servowarm who don't sell parts to the public or didn't maybe they do now however.

To open the valves just move the lever on the valve to the manual position.

 

[bongos]

If your getting power at the gas valve and the pilot is still lit then the valve is faulty.

You'll have a job getting hold of one of those valves which is just a basic Honeywell gray button valve with a modification made for Servowarm who don't sell parts to the public or didn't maybe they do now however.

To open the valves just move the lever on the valve to the manual position.

Tried opening the port valves manually and nothing. Boiler still not firing up. Both valves appear to be operating correctly. Does this leave the likely candidate as the gas valve? Is it worth replacing on this boiler or is it maybe time to invest in a new one? A gas valve is definately to be left to the professionals anyway!

 

[scottpaulwilson]

Does anyone know the flow and return pipes on this boiler or have a picture or manual?