British Gas - SpiroTrap Magnabooster

[CaptainWentworth]

Bit of background- we bought our house in March and knew at the time the boiler was old (Worcester 240) and would probably need replacing sooner rather than later. The previous owners made a big song and dance that it had always been covered by a British Gas agreement and regularly serviced, and we decided to continue with a BG Homecare 100 plan just to make sure we could keep the boiler going until we got round to replacing it.

We've had a problem with it since the weekend in that the hot water won't come on (it's a combi) except out of the utility room tap nearest the boiler. The BG engineer came out yesterday when DH was at home and said the problem is the heat exchanger being clogged with deposits so that it overheats and cuts out. He can replace the part for free under our agreement but said the new part won't be guaranteed unless we buy a SpiroTrap Magnabooster - he promised to email a quote for this but we haven't received it yet.

I can see that such a device would be a good idea with a new boiler to keep the system free of sludge etc., but I can't see the point of buying one when we intend to replace the boiler fairly soon anyway. Apparently we could still use it with a new boiler but if it's so essential don't new boilers have this sort of thing built in? I'm inclined not to buy it but am a bit worried about BG weaselling out of bits of the Homecare agreement if we don't fit it.

Any thoughts? I'm new to home ownership so am on a steep learning curve when it comes to this sort of thing!

The Spiro is an excellent product. It traps circulating particles that can cause a blockage in the primary circulation. Combined with a chemical clean it may save the trouble and expense of a powerclean. Ask the installer to show you how to vent out the sediment it has trapped.

Older heating systems, especially those that have, or used to have, a boiler with an iron heat exchanger and/or a feed and expansion tank in the loft, often contain a lot of sediment and particles. If they have not been treated with a corrosion inhibitor they will continue to create more corrosion particles as the steel raditors corrode away from the inside. This sediment can cause blockages and it sounds like yours have.

A Spiro will cost about £100 from a merchant. An independent plumber might charge you £50 to £100 to fit it (it is not a boiler or gas part so does not require a gas engineer). It will be interesting to know what BG hope to charge for it.

BTW I would also top up the corrosion inhibitor chemical while you're at it. The cost of the chemical, by a good maker like Sentinel or Fernox, is about £15 as a DIY job, but the installer has to make a living. With luck, there will be a label stuck or tied to the boiler or tank saying what brand it already holds, and when it was put in. Sentinel's latest product, X900, is a sediment-loosening material that, like a detergent, helps old sediment to circulate so that it can be trapped in the "filter" if you have one. It is not as powerful as a thorough clean, but I think is worth having. The advantage is that you add it to the system and don't have to drain it out. You can release the accumulated particles that have been trapped in the Spiro. You can also get a chemical to wash away limescale deposits.

It easy for a DIYer to add chemicals to an older system with a feed and expansion tank in the loft. A modern sealed system is more difficult.

p.s.

if the reason for your fault is that sediment deposits have clogged the exchanger, I think it is reasonable for them to say they will not keep fitting new ones if they keep getting clogged because you have not taken steps to tackle the sediment. Hence the conditional guarantee. If you are going to fit a new boiler in future, it will do nothing but good to have a spiro already as it will reduce the amount of sediment. The boiler maker's guarantee will not cover damage caused by a dirty system. It causes blockages and wears out moving parts such as the pump.

Thanks very much for that comprehensive explanation PigletJohn! (I was hoping you might pop up with some advice). It sounds like we should get the trap then- was hoping not to incur any extra expense at the moment as DH is between jobs and everything seems to need doing at once! However perhaps we could get someone local to do it for less- I have seen figures around £250 for the BG price when Googling but still not had an actual quote yet. Just hope they won't be arsey about the guarantee if they don't fit it.

Will think about the corrosion inhibitor as well- again was hoping we could leave all this until we replace the boiler. House is Edwardian so god knows how old the pipework is. Can't remember seeing a label on the boiler but it might be under the cover. Also not sure we have a tank as it's a combi, or will there still be a cold water tank in the loft? I'm ashamed to say I've never been up there myself as I'm too scared of the very rickety ladder!

If it is a combi, it is probably sealed. In this case there will be a pressure gauge on the boiler, perhaps behind a flap, reading about 1bar

If the pipework or radiators are old, an expansion tank may still be in use as the pressure may cause leaks (I have one, because of the simplicity of maintenance, and my new boiler has a stainless steel exchanger, which I am sure will be very reliable)

BTW Sentinel X100 is a good inhibitor.

Yes there's a pressure gauge on the front; I suspect there may not be an expansion tank as there was a slight leak from the water supply to the boiler when we first moved in and this made the pressure drop- would an expansion tank have neutralised the effect of the leak? I'll get DH to ask about rust inhibitor when the fitter comes back anyway. Thanks again for the info!

pressure drop from leak means it is sealed with no expansion tank.

I've just seen the quote - £269!

A bit on the high side but BG are never cheap.

I would have thought £200 would be OK

See if you can find a well-recommended local plumber who will fit exactly the same thing for enough of a saving to make it worthwhile, if so, you can spend the difference on Sentinel Inhibitor X100 and the new cleaning aid X900 (make sure he knows that you don't drain X900 out like most other cleaners). It is easier to tip chemicals down the pipes when they have been opened to fit the device.

There are other "filter" devices on the market at similar prices, but the spiro is mostly made of solid brass, not plastic, and one of the other popular brands has a poor reputation because it tends to leak.

I think the fernox tf1 is the best filter, the magna cleans are good, the magna booster don't seem to remove much sludge.
I think British Gas charge £269 to £360 to fit a magna booster depending on what system you have.
You can buy a filter from amazon £85 and get a local engineer to fit for £80-£100.
www.amazon.co.uk/dp/B0044YUZ80/ref=as_li_qf_sp_asin_til?tag=earnitonline-21&camp=1406&creative=6394&linkCode=as1&creativeASIN=B0044YUZ80&adid=02BW8M3GM83ZRQFAM343&

Magnaclean has a poor reputation for leaks. That's why BG stopped fitting them, they were losing money on callbacks and replacements.

As this thread has been revived I might a well update you on the outcome- in the end no spira whatsit was fitted, as the BG technician who came (a different person to the one who attended the original call out) found that the problem was actuall due to a failed rubber diapragm thingy between the hot and cold water bits of the boiler (I think- cant quite remember where it was). So was repaired under the agreement and boiler is still going strong, touch wood! Bit worrying that the original person didn't spot this though.

Anyway when we finally do get the boiler replaced, we'll look at the whole system and probably get a trap then.