Problem with Bosch Worcester Greenstar 24 Ri Boiler

I haven't had this problem but W-B have a good repair service. I would recommend calling them out. And I don't recommend switching off at the mains. The fans on some W-B boilers are prone to failure and need running regularly.

Is the clicking noise you hear that associated with cooling down or more like a relay on the control board opening and closing?

Similar sort of problem with the same boiler, yes. Turned out to be the cheap and nasty Chinese relays they use. Try exposing the control pcb and gently tapping it whilst listening for the characteristic relay 'click' followed by the pump cutting out. Then you'll know for sure it's a relay. However, sometimes there's no 'click' but the same thing happens anyway. In both cases, it's a relay. Even when the relays are energised and the contacts appear closed, they can still be open circuit as they often don't close with sufficient pressure to pass current. If Worcester-Bosch had used decent relays, it wouldn't have added hardly anything to the final price, so it's a shame. A service bod won't bother trying to trace a faulty relay, however, he'll just swap out the whole board (90 quid odd) and charge you for that plus the labour etc. If you're handy with a soldering iron, you can save a worthwhile sum just replacing the duff relay(s).

Many thanks for this advice. I am not up to much with a soldering iron and think I will probably discuss it with the CH engineer who installed it to start with.

No it is definitely not a cooling noise and it sounds louder and more like a technical problem inside the boiler. Not sure what could be causing it.

Thanks Mark, I will probably end up taking that advice.

Proper hate boiler problems as you never know how much it'll cost to be put right! Mind you don't trust BG though as I read that they like to turn a modest fault into a new boiler sale for their commission!

Instead, try asking a local heating engineer for help/advice. It may be something that they can fix quite easily and quickly - if you're stuck with who to ask, try STL Heating because they were very helpful to me and they didn't mess me about either.

lying newsgroup spam for STL

Have you got TRVs on all rads? and if so is there a bypass valve and is it working OK.

Basically the pump is running on unable to lose the excess heat possibly because the bypass valve is not opening?

Bugger - did not spot this was a vintage thread and even one I'd replied to before! DOH

ere is also a lot of clicking coming from the boiler.

The whole electrical wiring circuit associated with the boiler and the boi ler itself needs to be checked. Sometimes soon after the clicking noise sta rts the boiler stops working.For your safety and the safety of others aroun d you if you are not qualified never remove the boiler cover and tap on the relays as stated in previous posting. Taping on the printed circuit board relay might cause damage to the board electronic components or circuits.

Thousands of Worcester Bosch boilers repaired and serviced. Electronic engineer and Electrical Engineer Gas Safe registered engineer before working for Worcester Bosch, whilst wor king for Worcester Bosch as a boiler breakdown engineer and currently a gas Safe registered engineer. Mohun 07737845657

I suppose he has probably fixed it in the two years since posting, but just in case, what practical tests would you suggest?

(keep in mind this is a skilled and knowledgeable DIY group - posts that simply suggest "get a man" tend to get laughed at here).

If you have got useful things to contribute, let's have them.

Otherwise read:

replying to John Rumm, Tony wrote: have this problem, last night with water/heating off boiler was still starting/clicking. luckily engineer visited this am and was able to hear noise. He spoke with Worcestor boilers support and they say its likely to be voltage leakage triggering the boiler/fan and have suggested fitting a capacitor to solve problem...and if that doesnt work then new board. Will post update when i know its fixed

If it does turn out to be a PCB, then talk to Geoff at

Chances are he will have a remanufactured board to swap at a fraction of the WB price.

With ours (same model) it turned out to be a burned/melted wiring harness subsequent to a seal failure.

I got a fixed price repair and they rebuilt most of the boiler.

replying to Mike, Grannysmith wrote: I too have a Worcester Greenstar Ri it is 8yrs old , it is making the same clicking noise my man was going to have a word with the Worcester dealer but as yet no comeback. It is making the noise all the time now but only when the heating is on not the water

Read the bloody date of the original post !! (Three years ago), and please use a proper newsgroup reader, not that pathetic forum.