DIY Doctor UK DIY Forums

I would like some advice if possible, as I'm no expert on central heating but feel I've been ill advised.
I had a new boiler installed Mar/Apr this year by a Gas Registered plumber only because of it's age, otherwise the whole system was working. The hot water system was working fine but the central heating wasn't used until October. When it was switched on the central heating, the radiators downstairs were cold, but the rads upstairs were warm but not hot. I contacted the boiler installer who came out & suggested my pipes needed replacing due to them being a 'single-pipe' system and would never be any better. He didn't mention that there could possibly be a problem with the boiler.

I also had a 2nd opinion from British Gas as I have an insurance policy with them. They suggested a £700 power flush but they couldn't guarantee the problem would then be sorted. They couldn't look at the boiler as it was under warranty.

So I went with the new pipes. I was quoted £780 for new pipes, but £1780 for new rads as well as pipes. As you can imagine, the disruption was horrendous as I have 3 bedrooms with laminate flooring. A friend of mine kindly agreed to lift the flooring & relay it so the plumbers wouldn't be responsible as I had a feeling they weren't carpenters!

So having had all new pipes & radiators (I thought it might be best to do that at the same time as the system was best part of 40 years old) - the problem of the cold radiators downstairs was still there. You can imagine how furious I was. The plumber then tried to tell me that the boiler had been overworked due to the one-pipe system & that boiler engineers (Worcester Bosch) would be coming out to have a look at the problem. They then found that the heat exchanger was full of silt from the previous pipework as it hadn't been flushed before the new boiler had been installed. So when I'd switched on the central heating the sludge got pumped around the house & into the boiler. I had a new heat exchanger installed & the rads are now working fine.

I wasn't charged for the new heat exchanger (the plumber reckoned he'd call in a favour as he knew them). Really? Do Worcester Bosch dish out heat exchangers & engineer visits for nothing? The day after the boiler engineers visited, I mysteriously needed my header tank removing & replacing with a pressurized version. When I asked why - "it's all part of the boiler installation so you won't be charged". Strange that isn't it? If that was a part of the boiler install, why wasn't it done in April at the same time as the boiler?

There is still silt in the system as at least one radiator has stopped working since. When I queried this, I was then told to knock the TVR with a hammer to dislodge the muck. That did work but I'm now wondering whether this remaining sludge is going to continue to cause me problems. The plumber says he's put some more chemicals in to prevent this but is that adequate? When I asked the plumber why he hadn't flushed it, he said that he couldn't have flushed a 'single pipe system' as it doesn't work. So he had just put chemicals in to break down the sludge.

I am now waiting for the £1780 invoice- but feel that I was badly advised. If the system had been flushed before the boiler had been installed, I wouldn't have had the problem. If the engineer had checked the boiler before advising me he could have seen that the heat exchanger was faulty. I realise that a single pipe system is not efficient but I do think I was badly advised and would like to challenge the plumber on the bill when I get it. I would be interested in your opinion.

To be honest I am surprised your heating engineer agreed to fit a new boiler on a single pipe system. This style is outdated and is known to have issues. Maybe he genuinely believed it was not necessary to replace it but I should have thought he would discuss the pitfalls and recommend new pipes and radiators when fitting a new boiler.

Leaving a system full of sludge is not acceptable. It may be difficult to flush a single pipe system, but that does not stop anyone removing the radiators, taking them outside and flushing them manually. Incidentally, has anyone suggested fitting a Magnaclean? They remove almost all of the black sludge which damages heat exchangers. Many engineers won't fit a new boiler on old pipework without one.

It's quite possible the boiler engineer would fit a new exchanger. After all, there was no guarantee the original wasn't faulty, and he would probably decide to fit it FOC partly as an act of good faith.

the heating engineer did mention it would be good to replace the rads while he was doing the boiler but never mentioned anything about potential problems with a single pipe system & the new boiler. I didn't go with the rads as it wasn't urgent. No Magnaclean has been mentioned. According to the boiler paperwork, the warranty on a the boiler would be invalidated if a flush hadn't been done & the heat exchanger affected by sludge.
Do I have a case to challenge the bill when it comes?

Offering advice in your particular instance is awkward because obviously I only have limited information but challenging a bill can be done if you have lost out in some way due to the way the installation has been undertaken.

IF you have been billed for work that has not been done or have had to pay for repairs that were only necessary because of something the engineer did or didn't do then maybe you are entitled to a reduction in the total.

You might argue the installation has taken longer than it should and therefore the upheaval has been greater than it should and on that basis you could be entitled to some form of discount.