Continuous heating = dead ACB?

If I turn my boilermate 2000 off, leave it unpowered for a while and then turn it back on, all is well for a while but as soon as I draw hot water the central heating comes on full blast and stays on regardless of the clock or thermostat setting. I suspect the control board is kaput especially as the LCD is completely blank whatever button I press. It looks fairly straightforward to put a new one in but I am reluctant to do so unless I'm sure it fixes the problem (the ACB seems a tad pricey), so to put my mind a rest a little I wonder if someone could answer a couple of questions:

Do the boards just break, or is there likely to be some external problem that should be checked out first.
What do the jumper settings do, the manual says use positions 1, 3 & 4 but my boilermate has only position 4 and must have been like that since new 8+ years ago.
The board has four LED (one per pump plus one not used), all of mine are lit all the time, even the 'not used' LED. Is this normal?

Anything else I should be concerned with?

Many thanks for any help ...
James

Jumper settings are very important.
Your PCB has gone.
Power surges / lightening are the main causes.
DO NOT TOUCH THE NEW PCB use gloves or what have you.
Mike
MGC/H2O
Norfolk

James,
It reminds me the situation with old Sky boxes when you have them on for years then decided to change some wiring's unplugging box from mains. After that box doesn't start. It is electrolytic capacitors issue. Check my answer here how to fix it: https://gledhill-repairs.forumotion.net/t957-boilermate-2000-ignores-store-satisfied-temp-t1_off#3035
I had nearly the same problem: https://gledhill-repairs.forumotion.net/t969-pcb-fault-fixing
Unless correct jumpers fix the problem(but I suspect you had working unit with the same settings for years and didn't touch jumpers)

scorp wrote:James,
It reminds me the situation with old Sky boxes when you have them on for years then decided to change some wiring's unplugging box from mains. After that box doesn't start. It is electrolytic capacitors issue. Check my answer here how to fix it: https://gledhill-repairs.forumotion.net/t957-boilermate-2000-ignores-store-satisfied-temp-t1_off#3035
I had nearly the same problem: https://gledhill-repairs.forumotion.net/t969-pcb-fault-fixing
Unless correct jumpers fix the problem(but I suspect you had working unit with the same settings for years and didn't touch jumpers)

Hi Scorp,

Where can you get these capacitors from ?
Sounds like they could be a possible solution to my issue

Here it is(don't pay attention on the values on the pictures):
220uF x 25V
10uF x 50V
47uF x 50V
or from Maplin

Excellent, i'll get some ordered up

Thanks for the advice I've replaced the caps and now have both a working spare and one on the boilermate.

I ordered parts from RS and got five of each capacitor for a total bill of around £4. The part numbers are:

3150552 220 microF
3654240 10 microF
572198 47 microF

Not bad eh, £400 worth of boards fixed for £4!

RichardJ wrote:Thanks for the advice I've replaced the caps and now have both a working spare and one on the boilermate.

I ordered parts from RS and got five of each capacitor for a total bill of around £4. The part numbers are:

3150552 220 microF
3654240 10 microF
572198 47 microF

Not bad eh, £400 worth of boards fixed for £4!

Richard,
That is really good news. Glad that my advice helped someone

I seem to be having similar problems with my Boilermate 2000 where my heating started coming on at random times.....
I checked the ACB, all 3 pump LED's were constantly on and the digit readout was "ON.". I turned the power off and left for a few mins but the digit readout now doesn't come on and pressing the buttons does nothing. The 3 pump LED's still on. Also, the heating now seems to be permanently!

Order now placed with RS so hopefully this will be a cheep fix.

One other thing that's not related was that I noticed was that my GlowWorm boiler's thermostat was not set to max. Is this something I should change as the manual says the boiler should be set to max?

Main ACB has failed.
And YES
The boiler stat needs to be on max.
As the BM 2000 will tell it when it is happy.
Oh and you use more gas having it on lower.
Mike

Another processor brought back to life by changing 5 caps. Thanks

Weeguy wrote:Another processor brought back to life by changing 5 caps. Thanks

I'm glad it helped people save some money :). My boiler has been working for 7 years since I fixed it by changing caps.

The caps worked for me too, it's a 16 year old controller that now works again and doesn't give undemanded heating. Thank you, particularly for the part numbers.

Hi all,

I have the same problem outlined above (heating stuck on despite timer and thermostat set to off).

Is changing the caps straight forward? Is there anyone that has done it that could provide a quick guide please?

Really want to avoid having to drop hundreds on a repair with everything going on at the moment!

Thank you

I can repair the acb for you I also offer a reconditioned ACB exchange so you get a solution as quickly as possible.  Have a look at my website for more details:  https://murraymartin.yolasite.com/purchase-page.php

repair £45 exchange or £100 for reconditioned pcb with £45 refund for the faulty board when returned to me. 

Unless you have some experience and the correct equipment trying to repair these pcb's can result in the pcb being damaged quite badly.  Regards Murray