Kevin's Combi.

[KevinM67]

A quick update on this (via my partner who met the engineer)

You seem to know your stuff Pots, as the guy effectively asked the same questions.

The pressure valve needs replaced.

The water is apparantly not reaching maximum temp - he thinks this is due to to the heating plate being covered in sludge - which is also causing it to overheat then cut out.

He's coming back next Tuesday to do a chemical clean and replace the pressure valve - however, he's made a temporary fix and the system seems to working fine at the moment.

His charge is really reasonable and has included his visit today within it.

And yes, we have agreed to get it annually serviced - as we don't want the same problem again at this time of year.

Thanks for your advice - myself and the better half really appreciated it.

[KevinM67]

Kevin another thought for you.

If your repair man starts talking silly money you might consider getting the manufacturer in.

If you boiler is under ten years old Ideal do a fixed priced guaranteed repair for £275-00p all parts and labour. I have the phone number if you need it.

Sorry I forgot to include this in my previous post.

I'm thinking our boiler must be near the 10 year mark or probably over it as it was in the house when we moved in nearly 8 years ago.

I've no idea how long they are expected to last - although the engineer stated that once he's done the necessary repairs it should last OK for another couple of years.

[Potstubsdustbins]

Glad your sorted, seems you got lucky and got a decent bloke, get his card and keep it safe there are a lot of rogues out there and if you find a decent guy you want to be able to contact him next time something goes wrong.

Yep after testing the resistance on the overheat stat the next thing to go for is the plate heat exchanger, the gaps the water has to pass through are only a millimetre wide so it can get blocked easily.

As to how long boilers last these days, a couple of clues Ideal won't touch it if its over ten years old........ I have a landlord I do a lot of work for and his instructions are if its 10 years old and the repair is going to cost over £300 put a new one in........... Finally 'Which magazine' in their report said expect them to last 10 years also expect to pay on average £1000 on repairs during that time.

For private customers we always recommend either Worcester or Baxi depending which one is offering the best guarantee at the time. At the moment its Baxi with 7 and 10 year guarantees, subject to terms and conditions.

Now I am going to tell you off. Stop bleeding the radiators unless it is necessary, yours is what we call a sealed system, bleeding the radiators adding fresh oxygenated water is what causes the corrosion within the system thus blocking the plate heat exchanger.

If I can help mate let me know.

[Bigmallly]

Potty, I wonder if it would be wise to point out the symptoms at which us mere mortals would consider bleeding the rads.

[Potstubsdustbins]

There are only two ways to get 'air into' a system. The symptoms are always the same the top of a radiator or radiators will go cold and you have to release the air using your rad vent key.

If it is a traditional system with a feed and expansion tank in the loft say a badly designed system can draw air down the open vent or corrosion can generate hydrogen gas.

On a sealed system such as a combi air in the system usually is a sure sign of corrosion.

Either way you should seek advice before the system deteriorates to a terminal condition the first sign of which will be the rads pin holing. Do not get the rads replaced until the problem is cured they will only go again usually within a year.

One of the tests I do is to place a metal mug upside down over the air release valve and vent the rad. I then apply a flame in the upturned mug if the match goes out its air being drawn in from outside somehow. If it ignites with a pop its hydrogen a sure sign of heavy corrosion.

[Potstubsdustbins]

When I find a case of corrosion I have a device called a Magna Cleanse which contains two large very powerful magnets. We cut this into the return pipe of the system and add a chemical cleanser, turn off all but one of the rads and fire the boiler driving the water through just the one rad. Whilst one man operates the valves on the machine the other takes his rubber mallet (well there had to be an hammer somewhere) and gently bumps the bottom of the rad to move any stubborn sediment. This travels round the system getting caught by the magnets before it can get into the boiler. Then turn that rad off and proceed to the next one. Once that's done we run the hot water side of things to remove any dirt/debris from the plate heat exchanger.

Finally we remove the machine and fit a Magna Clean a single heavy magnet that will remain in place, top up with inhibitor and bobs your auntie complete protection.

Not cheap it costs anywhere between £350 and £400 but it has never failed me yet.

[KevinM67]

I've gave the other half a telling off on your behalf Pots.

[Potstubsdustbins]

^^^^^^^^^^^^^Oh I bet you did, just like I tell SWMBO off......................fine chance.

[Nannysally99]

My Baxi back boiler is 34 years old potty, still doing ok - fingers crossed

[Potstubsdustbins]

Lucky you, the boilers of that generation had cast iron heat exchangers and were very simplistic by todays standards, the downside is the are so inefficient they eat gas.

One word of warning at that age dedicated spares will be hard to come by if not impossible. The gas valve will probably be a 24 volt Honeywell they are no longer made so if that goes its a new boiler. Still I think you can say you have had good value for money.

[KevinM67]

Can I just say that my combi-boiler has accumulated more posts than any of the threads that I have started on here.

[Nannysally99]

For sure, we have had our money's worth. One wrong move with this boiler and it will get replaced for sure. So looking forward - not - to the upheaval it will bring.
Our gas bills are still quite reasonable.
Sorry to have hijacked your thread Kevin, but with a resident heating engineer, you just got to expect it lol

Lucky you, the boilers of that generation had cast iron heat exchangers and were very simplistic by todays standards, the downside is the are so inefficient they eat gas.

One word of warning at that age dedicated spares will be hard to come by if not impossible. The gas valve will probably be a 24 volt Honeywell they are no longer made so if that goes its a new boiler. Still I think you can say you have had good value for money.

[Aberdeenplotter]

Can I just say that my combi-boiler has accumulated more posts than any of the threads that I have started on here.

I think it's a source of fear for most of us that we need to get a new boiler. We bit the bullet last year having risked a couple of years after being told by Scottish Gas that they couldn't guarantee to be able to get spares for our Vokera boiler which at that time we had owned for 12 years or so and it was in the house when we moved in. Even tempted fate and put the gas board off from coming to do the annual service in case they condemned the boiler putting us in the position of perhaps having to buy from them and boy they are mega expensive.

Anyway, new boiler - Baxi installed with 10 year Guarantee. Wonder though if we have put our head in a noose for when the 10 years is up. Who will take on a 10 year old boiler on a maintenance contract when the guarantee expires?

[veggiechicken]

My boiler is 10 years old - Worcester Greenstar HE system. I have a maintenance contract with the CH engineer who installed it. He services it annually and the contract covers callout and replacement of any bits that stop working. Its very reassuring to know that, when there's a problem, he'll pop up and sort it, and he lives nearby............and his name's Colin

[KevinM67]

Sorry to have hijacked your thread Kevin

No need to apologise to me Sally, it's not my thread - it's my 'more popular than me and has more posts than any of the threads I've started' combi-boiler's thread.