Can a pcb be reconditioned properly?

[pleasehelp]

My plumber has spent hours on my alpha 240x boiler recently, he can not find why i have an intermittent fault on my ch and dhw. I had the main pcb reconditioned but the plumber and alpha think that its not possible to do it and want me to fork out £170 plus fitting for a new one.

Cheers for any help.

 

[corgiman]

many will say NO

many will say yes

but the proof is in the pudding aint it

 

[Gasguru]

A board can fail with a just single broken joint or a burnt relay contact - so re-conditioning is often possible however the quality of this service varies considerably between the companies providing the service and there are some real roques out there.

The industry does however frown on the practice of fitting recon boards and the gas regulations are a little ambiguous as to the legallity of fitting them. It comes down to each gas installers own view.

No one bats an eyelid getting on a plane despite the fact half of its reconditioned.

Whats the symptoms of the problem - Alpha 240's are one of the best combis ever made - I've yet to change a board in one.

 

[pleasehelp]

It all started two months ago, moved in to a new property, boiler working fine for 2 weeks, then it has been working intermittently since.

Plumber came and diagnosed ignition pcb. Replaced it - no joy. Removed and put old one back in.

Then diagnosed main pcb, cost of £170 plus fit. I didnt want to spend that much so got the board reconditioned with cet in watford. He came back and fitted them -no joy!

Then diagnosed it as the temp sensor, replaced - no joy, again.......

He spent ages on phone to alpha tech team, ran a lot of tests for continuity etc. The only thing that he and alpha think it could be is the main pcb. They want to try a new one.

Sometimes the boiler will work fine all day, sometimes not at all and sometimes randomly.

I thought it may have been a loose connection, because after fiddling with the connections on the boards i got it to work a few times, but this does not always proove succesful. Waht are the chances?

Another part of the problem is that sometimes when hw is working it runs at below temp even when turned up high.

Any help will be much appreciated.

Interesting that you say this is a good boiler, not what my plumber said!

Cheers

 

[DIYsaster]

another thing to consider is that even though problems like dry joints CAN be repaired, the rest of the board is still X years old and whats to say another component won't fail on it in a couple of months. i work for a BIG gas company and we do not use recon parts for that reason. my advice would be; be SURE it IS the board first, go for a complete new one-i know it'll hurt your wallet, but at least you will know it'll last. also 170 quid sounds a little steep-have a shop around if you are confident enough

 

[pleasehelp]

Thanks, plumber has said that changing the main pcb is the only thing he can do now. Im not sure it is that, but what do i know. He only wants to change that because he does not know what else to do. How can i be sure its the board, i dont know if he is sure!
Cheers

 

[ChrisR]

Has anyone checked the microswitches, they do go intermittent. I mean the two on the diverter.

 

[pleasehelp]

micro switches have also been checked.
Any other ideas?

 

[Gasguru]

Does he actually repair boilers day in day out or is he a plumber?

If he thinks Alpha 240's are bad boilers he can't work on many boilers so I'd find someone else.

Talk to Geoff at CET - if its a bad board I'm sure it will be swapped without any problem.

You need to describe the fault in more detail. What lights come on? Does it always fire up or is the water just not hot enough.

Common faults when the boiler gets to this age are the fan requiring cleaning, intermittent flow thermisters, sticking diverters.

With a hot water demand does the left hand pipe under the boiler get hot - if so the diverter needs reconditioning/replacing.

 

[mehran]

wait a sec...

you have this fault, so you got a recon main pcb but the same fault is still there. if that is the case then i highly doubt that the old and the recon pcb has the exact same fault.

pcb are not refundable, you get it then your stuck with it

i would send the recon board back as faulty and get them to send out a different recon board, i think they will do it at least once to just to be sure that they have not f up.

paul barker is the alpha expert around here.

alpha are a good boilers in general

 

[Paul Barker]

Never changed a pcb on one of these. Good boilers generally, but any boiler can do this to you. Never had a bad pcb from CET. Have sent them some right old nackered boards out of obscure old boilers and they've sent them back working.

If fiddling with wiring loomb cures intermittent fault that looks suspect doesn't it?

Difficult to home in on the fault though in your situation without being there.

A failing aps can go wrong intermittently, I would have my test meter on it and wait until it fails, see if aps drops out at moment of failure.

Hot water problem is almost certainly primary side service kit aslong as dhw side pushrod makes microswitch and maintains it over time, and doesn't leak out of the gland where the pushrod emerges. Make sure that when boiler drops out the primary flow microswitch hasn't dropped out.

If it has the black thermisters these are normally OK, long lasting, if they ave been replaced at some time with white they are bullet proof. If they are red or blue they definately should be changed to white. Grey were used for a while those are also OK normally.

There is usually a full set of pcb's forthese for sale on eBay. Ihaven't bothered to buy them as the two genuin alhpha ones I have in stock have never been called upon.

If fault is same after pcb change, considering how rugged the pcb is, I would definately be looking elsewhere, revert back to original pcb and look somewhere well away from the board. Put the cover back on it, the fault is back in the boiler somewhere.

Look I'm not saying you don't have a real tricky fault, I'm just saying don't get hung up on the pcb. I could lend your corgi registered engineer one on production of his credentials but I honestly think it's a waste of postage. Get him to talk to me if you want send me details my email address is in the profile.

 

[werewolf]

Have worked a lot of theses boilers and never had to change pcb`s.
Sounds like your engineer is totally lost and is just throwing parts at it in a hope to fix.
When he is checking the aps is he just listening for the "click" or actually checking with his multimeter.Have had seversl switches which sound right but don`t actually switch.has he cleaned venturi on fan?

Paul

 

[Agile]

"Checking" an APS or microswitch is not just a matter of doing a resistance check on the 10k range.

To be fairly sure it operating correctly the contact resistance has to be measured on several switch operations to be sure its consistant and less than say 0.3 ohms.

If your plumber does not know the difference between an amp, volt and ohm ( and ideally a Henry ) then he is not going to very good at fixing a boiler.

Tony

 

[JohnD]

that should be easy

(sorry)

 

[pleasehelp]

Thanks for all your help guys. Sometimes the boiler works fine, both dhw and ch work fine, other times it doesnt work at all. Sometimes the boiler works but dhw does not get very hot.

The problem seems that the fan does not go into the high speed, which then doesnt work the pressure switch? which then doesnt open the gas valve i think....? So there is a problem igniting.

Sorry what is aps?
Plumber not removed fan or cleaned it yet.
Or done anything with the diverter as far as i know.
I cant find loose connection on wiring loomb.

When he has been round he has tested everything under ths sun for continuity, which is why he cant find fault.

Thanks again