Help! Engineer doesn't know what's wrong with boiler says replace it

[Dottierichardson]

Have a 6-year-old Worcester Bosch condensing boiler Greenstar Junior 28i Mk1v. Was working fine but the pressure was starting to drop a little and needed repressurizing more than normal. Had a guy in to service it. Gas Safe, seems very decent.

Came to service boiler and said needed a deep clean. Broke the seals and cleaned it, but pressure still dropping when heating off and climbing up to 2.2, dropping again and then climbing to well over 3 in the red zone. Guy thought it was an expansion vessel problem. Came back again and re-pressurised the expansion vessel, checked the PRV and the Schrader valve and anything else on/in it that might affect pressure.

Says readings all normal but fault still there and doesn't know what's wrong with it so can only suggest new boiler! Obviously that's drastic and expensive...any advice? Worried about having no heating but don't want to replace a boiler if don't absolutely have to do it. Says can use hot water in the meantime just not the heating, but think pressure too low to safely run hot water. Rang WB but they charge over 300 just to come and look at it and could offer no advice. Don't know what to do next, do I just cave and agree to buy no boiler and find cash to do so or is there another option? I've never heard of anyone not knowing what's actually wrong, is this common?

You would know when you pumped up the air tank whether the pipe was blocked. You would normally expect that as you started to pump, some residual water that hadn't come out when you drained the boiler would then come out. If the pipe is blocked there'd be no audible movement of water.

Everything you have described is an expansion issue. You only have to turn off the radiator you're going to use at both ends, then empty the water do the nut back up and turn it back on. Make sure the system pressure is at 1bar, turn heating on and see how your pressure behaves.

Also watch the pipe outside (the pressure relief pipe) to make sure it's not dripping as when they have discharged several times they can not re-seat properly.

You only need a qualified gas engineer to work on the boiler or gas pipes. The radiator pipes and radiators can be done by anyone. How confident/comfortable you are with doing this is up to you. It's no more work than a decorator removing a radiator to decorate a room.

If this works, it would be much easier and cheaper to fit an external expansion vessel than replace the one in the boiler. Even replacing the pipe can be quite a pig as the expansion vessel end is out of reach.

As for what your engineer said about no one doing this. Well, it's not something an engineer would do as he/she would be able to identify the problem without doing this, but it is something my husband (who is a gas engineer) suggests his customers can do as a temporary measure so they can wait for a day rate rather than overtime appointment.

It's a tricky time of year to get an engineer and I would expect a wait for a good engineer, or have to pay for an overtime appointment at night. But if the radiator trick works you can leave it like that until you've found an engineer you're happy with to fit you an external expansion vessel. Rough idea maybe max 2 hours labour plus £50-80 parts and VAT if they are VAT registered.

Good luck!

Makes no difference if system is on or off, as long as the radiator in question is turned off at both ends whilst you are emptying it.

Dobbinsveil thanks that's great, all we wanted was a way of running the system long enough to have a shower and warm the house up, while we sort out a proper solution. The engineer said we'd just have to manage until he's free again to replace boiler, which would be a few weeks but not sure want a replacement from someone who seems so vague about boilers. Don't want to be pressured into doing the wrong thing because the heating/water don't work. If we hadn't had some old space heaters we would have been really stuck last night and today.

It would be some extreme circumstances to need to replace a WB 28i Junior that isn't even 7 years old. DH fitted a WB combi last week, and it has a 7 year warranty. Replace the engineer, not the boiler!

Your DH sounds great, the problem is that there are so many boiler engineers listed and I'm sure loads/probably most of them are excellent, it's avoiding the ones that aren't. Also once you're uncertain about someone it's hard to know if they're being straight with you. Most of my friends are not that local, as moved here for work, but some friendly neighbours so will ask around and see who I can come up with. And will check out the forums as well.

Apparently I should appreciate DH more too

It can be hard to find a good engineer, unfortunately even dangerous ones rarely face any consequences from the likes of HSE, as they deem it not economically viable to prosecute if they agree not to do it again . You could try a local boiler spares shop, the staff may be able to recommend someone. Not in an official capacity, but quite often the staff will know the ones who do take on the challenge of repairs.

But on the plus, if the radiator trick does work, you can confidently tell an engineer what you need doing and their response will probably give you some insight. Generally speaking, replacing a boiler is easy, repairs you need to know what you're doing.

You have nothing to lose with the fixed repair. If they can't fix it, I'm sure you don't pay anything and at least you would know the other guy isn't at it.

I think they would do their best to fix a boiler that's only six years old.

My mum has a really good experience with a fixed repair for her boiler which was around 5 yrs old and they put several new parts and were there for hours.

I had a problem with my boiler that my service engineer couldn’t fix, so he suggested I contact the Bosch boiler people and ask them to send their own engineer. Between my engineer and theirs they replaced just about every part of the boiler and still it wouldn’t work. Eventually they found it wasn’t the boiler, but the short length of pipe going from where the gas came off the meter and the boiler. It was full of fine black powder which was formed over the years by a chemical reaction between the pipe and the gas ( I think that’s right) and it was blowing the powder into the boiler. They replaced the pipe and it solved the problem. Had to pay a bill of nearly £1K
, but my engineer said my boiler would be good for another 15 years as so many parts had (unnecessarily!!) been replaced in the boiler before they found the actual cause.

With the age of your boiler I would do either of the two things PP have advised; phoning WB for one of their approved engineers or a fixed repair from BG.

Thanks the dust thing sounds awful but what's driving me mad is that the boiler was working before it was serviced. It had tiny variations in pressure but nothing drastic. Now it still fires, the radiators are evenly hot etc but because the pressure variations are so extreme it's not possible to use it. Walkingthedog interesting your guy recommended calling WB I asked if I should do that and our guy said not to...also that they would want all sorts of records and was I sure I could dig them out and so on...

Still can't work the guy out he spent a lot of time on it, so seems an odd approach...It felt as if he was pissed off that there was a problem, but wasn't keen to explore other options and finally decided he didn't care unless we bought a new boiler. We know we didn't actively do anything to piss him off, we left the space clear and clean, offered coffee/tea/biscuits. Told him he could use bathroom. Left him to get on with things...we've had builders/electricians/fencing guys in before and everything's been fine.

I've gotten a recommendation from a neighbour and I've managed to contact the builder who did some work for us last year and he recommended someone too. But both are apparently very good so will be booked up for ages. So think it may be a cold Christmas. But sounds as if should consider WB again. Also think builder's mate - who's really good may be able to come out and drain the radiator.

Where in the country are you op?

I would be very concerned he didn't want a WB engineer to come out. They will be able to see whether the parts are genuine and fitted correctly without any paperwork. That would make me get someone in straight away.

Dobbins is absolute spot on, i was going to say the same only with a lot less detail.
Basically an obvious expansion vessel issue, replacing the rest of the boiler just for that would be crazy. In situations of this doubt the boiler itself should be drained and the ev and it's pipe removed if easy on the boiler. Then all flushed through and pressurised slightly lower than the cold heating pressure eg ev=0.8 and water charge=0.9.
If the ev is inaccessible then the radiator trick would provide external expansion, if that works then an external ev might be more economical if you have space somewhere.
It's possible that systems have air in them for years providing expansion volume. Then after maintenance the air is bled off as it should be. That gives the impression the work caused the issue, whereas actually it was hidden by a double fault.

The WB website has a list of approved engineers, I'd try for one of them to come out and have a look.

It's possible that systems have air in them for years providing expansion volume. Then after maintenance the air is bled off as it should be. That gives the impression the work caused the issue, whereas actually it was hidden by a double fault.

Thanks does the air get bled off just by working on the boiler? He didn't bleed the radiators or drain the system down or anything like that.

Dottie in that case it wouldn't be possible. But he would have had to drain and refill the boiler itself to check the charge pressure on the expansion vessel. Although given this engineer knows little, it's possible their confusion comes from doing it wrong.

Think he said he set the pressure for the EV at 1, as this was the recommended level. And that the readings were normal. But basically you're all coming up with other things that could be tried but weren't tried , and he said that nothing else would make a difference so clearly I need a more old-school engineer who's okay to have a go.

1 bar is ok for the ev, but my point is that if he didn't drain the boiler itself, the pressure in the ev is impossible to set.
Also for a contractor speed and predictability are essential as time is money. So all the time consuming things you can do yourself for free, but a heating engineer would have to charge a day or eat the cost. If he's not confident and has to replace anyway, who pays for the wasted time? At least a new boiler is obvious and easy to justify where the time went, also predictable.

I had a similar issue a few years ago and it was the pressure guage was out, quite spectacularly. A new one fitted and the issue disappeared. It's a cheap part so worth doing even if it's just to rule it out.

We also had British gas homecare for our boiler as it was 18 years old and definitely on its last legs. Thanks to them it lasted our first 4 years in this house and has just been replaced this summer.

Worcester Bosch boilers are great. We've had ours for 16 years, a week ago the heating stopped working but water was fine, called out WB engineer. £350 call out fee for repair including most parts, turned out that thermostat battery low, so didn't switch on heating! Engineer diagnosed problem, changed battery, did full service and only charged £150 for service. WB care very much about their reputation and are very unlikely to rip you off.

We had a similar
Problem with our boiler- same
Make- and about 8 years old. Actually I think it had a 7 year warranty so was just outside
It- check yours it might still be in date
We have a service
Contract with BG and I know most people slate them but I think we must have some
Good eggs round here. They spent about 4 days changing parts in the boiler ( mother board/ heat exchange etc) and also did a powerflush until it was sorted. We practically got a new boiler built - the people at Worcester Bosch were less than useless and didn't seem to know what the issue was so the engineer had to sort
It out for himself.

Definitely get a second opinion- a boiler that is only 6 years old should not need replacing...

Kayaking Was the £150 on top of the £350 or instead of? Glad you got it sorted. We know it's nothing like the thermostat, we change the batteries regularly and we also re-pressurise the boiler via the filling loop every 6 months or so...
Brigitsknickers did you have a WB engineer that was useless? or the people on the phoneline?

It was the Bosch people on the phone line that the BG engineers spoke to- absolutely bloody useless

Glad you've managed to get some recommendations. You won't be cold until Christmas if the radiator trick works.

The engineer probably was frustrated at the situation - it's unlikely to be anything personal against you. He went to do what would be a straight forward service and then hit against something he doesn't appear to have much experience in. He did say he couldn't determine the fault, rather than saying it was beyond repair. Just he couldn't repair it IYSWIM.

DH is in a fortunate position that he was trained by his dad who was Ye Olde Gas Board City & Guilds trained. Although his dad has since retired, he can still get advice from him. Not that he needs to much, but it's a back up that's a big advantage.

BG are variable. When my mum moved 400 miles away, we suggested she take out a BG plan because she was moving to a large city and would be taking a chance on just finding someone out of the Yellow Pages etc. But DH has also picked up a fair few customers after BG have gone in for a hard sell on a system that simply does not need to be replaced.