Potterton Puma 80 - kettling - advise please.

[harrietbalderstone1]

Hi there

I wondered if any experts out there could advise me.

I’ve got a Potter Puma 80, I’ve also got British Gas Cover, the boiler as it’s going hot and cold when we have a shower and in the colder months when we had the heating on the pilot light used to knock off.

I’ve called BG on about 8 occasions for them to sort it out and when they eventually turn up they fiddle with the boiler – they put 2 new pumps in in 18 months and the last engineer pumped something through the system (came out v.black, which she said was bad) anyway progressively the boiler has got worse – the last engineer who came said that the boiler is ‘kettling’ that the heat exchanger needs replacing and we would benefit form an aqua something that filters the lime scale out of the boiler. They also say that it’s a problem because the pipes are 15mm – which I don’t understand as the boiler was ok before with the pipes. As it happens all of the parts she says we need aren’t covered and will cost me about £500.

Anyway I’ve got a friend who’s a plumber and he said that we could give the heat exchanger an acid bath to clear it of lime scale and then put in a inline scale remover as the thing that the BG woman suggested are rubbish and cause the system to leak.

My friend said he’d do the acid bath and put in the inline scale remover all for a total of £120.

What I wanted to know is, does anyone think what my friend suggests will do the trick, if it will then surely BG will be able to do that and I’ll be covered. Or should I buy new heat exchanger but inline scale remover, but that will cost £500 and my plumber friend has Quoted about £1500 to fit a new boiler.

What I don’t want to do is :
Pay £120 for Acid bath etc and it not work
Then £500 to BG and it still not work

Can anyone help with what I should do?? It’s tricky as my friend wants the work and BG get commission for parts they sell….!!!!

any advice would be helpful

thanks

Harriet.

 

[JohnD]

I am a householder not a professional

If the water is black, then it is suffering from Magnetite sediment. This clogs the pipes and radiators and settles in the boiler causing knocking. It is iron oxide, the result of the steel in the radiators corroding in the water. (you may also have other problems that I don't know about)

The black sediment can and should be dealt with, it is easy and cheap to do a chemical clean (your plumber friend will know how, or you can do it yourself) as the chemicals only cost about £15 for the cleaner and £15 for fresh inhibitor. You do not need to use an aggressive acid for this. It is also very worthwhile to add a Magnaclean (costs about £100) which traps circulating black magnetite particles, both those loosened by the chemical (you can never rinse them all out) and new ones, preventing them forming future blockages.

I have used an acid cleaner myself on a couple of occasions on a very old boiler, but don't know how it would suit yours. If you are sure it has lime scale then I suppose that would explain the acid bath.

 

[harrietbalderstone1]

Hi John

thanks for the info. i think the BG engineer pumped this out when she came last - she used a rubber tube and foot pump, should really pay more attention and ask what she'd doing.

I really want to know if i should pay £500 for the new parts or if giving the Heat Exchanger an acid bath as plumber friend suggested would be sufficient.

thanks

Harriet

 

[JohnD]

The Foot Pump sounds more likely to have been to repressurise an Expansion vessel, nothing to do with cleaning out the sediment (which takes half a day or so)

I am a great believer in clean systems, so if yours is dirty, I would certainly start by getting it clean, and this need not be expensive (but it will be if BG do it).

Find out what chemicals and devices your friend plans to install, especially this lime filter you mentioned.

I am a householder not a pro.

 

[mickyg]

one thing I will say is don't waste £500 on this old beast.
Currently you are probably paying BG about £200 or more a year for insurance. IF you buy a new boiler with a 2 year warranty, you've saved £400 straight away, add the £500 and a new boiler doesn't look so expensive. I would recommend replacing it as this particular model is problematic, even more so when scale and sludge are involved.
If you replace the boiler make sure the installer flushes the system.

 

[palerider45]

hows the hot water on other taps, it could be scale but also could be a dodgy wax capsule these boilers don't have the usual diverter valve they have a wax capsule and can play up on hot water as well as heating, i would call b/g back and get problem confirmed before spending any money. In my experience of these boilers it could be a number of things before scale and sludge, i could list a number of things that go wrong with this boiler. Call b/g back to confirm.

 

[harrietbalderstone1]

I'll call BG and get them to confirm - i wanted them to give some kind of guarantee before paying for the parts but i understand that's asking a lot!!! especially from them who can't even turn up on time!!

the hot water seems fine when you turn it on but cuts out then cools down then starts up again so we spend more time standing out of the water when showering than in!!!

do you think that the Kettling will stop if the heat exchanger is given this Acid Bath my plumber suggested.??

he said he'd do and acid bath on the exchanger, run cleaner through the whole system then add the inline scale remover and charge me £120 for the lot....

does that sound like it'd work??

thanks

 

[bengasman]

If your friend is a plumber, but not a gasfitter/heatingengineer, he should not work on you heatexchanger.
It isn't needed either, a good start would be a chemical flush which you will find described in faq, together with other things you should know about your boiler.
bg are notorious for collecting insurance money, but not fixing the problem. Don't pay them for work, as a reputable local installer is likely to do a better job for less money.
Cleaning your system is a much,whether you keep the puma, or get a new boiler.
Nothing kills a new boiler quicker than a decade's worth of gunk in the system.
Installing a magnaclean after the flush would be a good idea too.
And forget about the limescale filter, that is not what is causing the problem.

 

[Agile]

In spite of what some will tell you, this is a manageable boiler by anyone who understands them.

Like all boilers, it does need to work on a clean system. BG dont cover dirt in a system on their fixed price annual cover.

Its easy enough to fix your boiler.

However, you plumber friend should not be touching boilers if he is not gas registered.

Tony

 

[baxpoti]

Replace the boiler or call in Heateam for a fixed price repair with 12 months warranty.

 

[Agile]

I dont think even Heateam will deal with a dirty system under their fixed price repair.

Tony