Wickes 2000 (Halstead Quattro?) Help!

[naffedoff]

Got a problem (or two!) on the Wickes 2000. Any help would be very much appreciated. Here goes...

Fan packed up and was replaced, all OK for a week or so.
Then we couldn't get any hot water but CH worked fine. Engineer came out and initially said it was the diverter and demonstrated the plunger pressing the micro switches which in turn fired the boiler, but no hot water came through. He then decided it was the PCB ('driver board'?). He tried a new one and also changed one of the micro switches but still no joy.
He came back a few days later and changed the diaphragm in the diverter and after fiddling about for a while we also lost the heating!! Cheers! He then said it was the ignition board. He tried a new one and guess what? Nothing! No heating, no hot water.
Now all that happens when you turn the heating on or run the hot water is you get a sound from the boiler as though something is running(??).
I noticed on another thread the operation sequence for this boiler and it says 'call for heat, fan starts etc.' I took the cover off and tried turning on the heating/hot water and the fan fails to start.

I'm at my wits end and freezing my t*ts off.

 

[chrishutt]

Maybe you should try a different engineer. Have you paid the guy? (and if so, for what?)

 

[Agile]

Really thats very disappointing.

Unfortunately there are some people who just do not have any diagnostic skills at all and all they can do is change parts.

There are some people who just do not seem to be able to carry out logical reasoning and I dont know hot this can be taught. Even my friend who is an Educational Psychologist does not know either.

Get a better engineer who will agree a no-fix no-fee charging basis. You should NOT be paying for parts that are not required and you should not be paying for time spent by an incompetent person who does not have the necessary skills for the job.

Tony

 

[naffedoff]

The only thing I paid for was the fan.
When the driver and ignition boards didn't work he put the old ones back in. He admitted he was at a loss to explain the fault and didn't charge us anything, which was a relief for my wallet, but we're still knackered for heating/hot water.

 

[ChrisR]

SUppose you follow the fault finding guide which is on the mfrs website?
It tells you to check that the overheat cutoff device is reset (button), and the pump overrun thermostat wiring.

Of those appear ok then you'd check the pcb connectors are connecting, diverter valve switches are connected OK, etc. There isn't all that much to check

 

[bogstandard]

Assuming the offending combi is a Halstead contact them direct.

 

[naffedoff]

SUppose you follow the fault finding guide which is on the mfrs website?
It tells you to check that the overheat cutoff device is reset (button), and the pump overrun thermostat wiring.

Of those appear ok then you'd check the pcb connectors are connecting, diverter valve switches are connected OK, etc. There isn't all that much to check

Overheat cutoff is reset. There was a layer white chalky stuff (??) between the pump overrun thermostat and the plate it sits on so I cleaned this off and replaced it, wiring seems OK (10V?), still nothing. What puzzles me though is that the fault finder leads you to the pump overrun for both DHW and CH yet CH was working when we first lost DHW.

 

[croydoncorgi]

The 'chalky white stuff' was heatsink paste, designed to transfer heat between the surfaces! It was supposed to be there!

From your description, the boiler is trying to run (sound when you turn on CH - is it the pump running - big lump at bottom of boiler? or fan - at top?)

Do you hear a click when a hot water tap is opened? What (if anything) happens next?

 

[naffedoff]

The 'chalky white stuff' was heatsink paste, designed to transfer heat between the surfaces! It was supposed to be there!

From your description, the boiler is trying to run (sound when you turn on CH - is it the pump running - big lump at bottom of boiler? or fan - at top?)

Do you hear a click when a hot water tap is opened? What (if anything) happens next?

Doh! What an eejit! I thought when I cleaned it off, 'Well how did it get there?' Most of it had crumbled away. What can I say? I'm desperate. Anyway, yes it is the pump running, the fan does not start. When hot water tap is opened the plunger on the diverter presses the micro switches so there is a click from the switches but no click as if the boiler is trying to fire.

 

[croydoncorgi]

If the pump runs and the OH stat is OK, the next thing that should happen (I think - not quite sure exactly what Halstead model this corresponds to) is the the fan should start.
Check for live on the fan terminals.
If it really is like the Quattro, there seems to be no water pressure / flow switch checking for pump pressure and water in system, so the only thing that could stop the fan running is a fault on the PCB or on the fan itself.

 

[naffedoff]

If the pump runs and the OH stat is OK, the next thing that should happen (I think - not quite sure exactly what Halstead model this corresponds to) is the the fan should start.
Check for live on the fan terminals.
If it really is like the Quattro, there seems to be no water pressure / flow switch checking for pump pressure and water in system, so the only thing that could stop the fan running is a fault on the PCB or on the fan itself.

The guy who came out tried changing the driver and ignition PCBs but with no luck. As I said earlier he replaced the fan the week before when that went and all was OK which makes me wonder if its a duff fan. But having said that the CH was working OK, we had only lost the hot water a couple of days later. Then he fiddled about with it and the hot water went as well! What should the voltage be at the fan terminals?

 

[ItsOverFlo]

thermister fault, easy.

 

[naffedoff]

There are 2 thermistors on the boiler. Will they both need replacing? I don't wish to question you judgement but is there any way I can test this for sure before I order the parts?

 

[ChrisR]

Call halstead for resistance values. The two thermistors are the same, so you can compare them, or even swap them over.
You seem to have , or have had, more than one fault; ItsOverFlo what's your thinking here?
The one called CH thermistor (see P7) is on the primary cct so could be in use to check the boiler temp overall so demise could affect both operations I suppose.

Do check that the overheat thermostat and pump overrun stat are making proper contact - ie dead short when shut.

 

[ItsOverFlo]

thermister faults can take out other parts, such as fan gas valve etc, trust me i seen it...