Page 1 of Does anyone know anything about combi boilers?

We`ve moved into a new flat today, and there was no hot water.  Further investigations led to the discovery that there is a prepayment gas meter and it had run out, so I went and topped it up, pressed the button etc, still nothing.  Mum suggested the gas may be turned off, and she was right, under the boiler is one of those funny taps with the long handle and it was off.  On turning it on, the pressure on the boiler immediately jumped into the red bit where its too much, and bounced between the two numbers there, and it makes a god awful clanking noise like someone is banging two saucepans together.

I was a bit worried because of the pressure going up so high and turned the gas back off.  But, can anyone tell me if this is normal if the gas has been turned off for a while (minimum 2 and a half weeks) before I look like a wally going and telling the estate agent in the morning?  Its a glow worm betacom 24C if that`s any help.

Thanks in advance :)

Don;t touch them with a barge pole. It sounds like there`s a air pocket in the system somewhere, and the boiler is trying heat air, hence the bouncy pressure gauge.

Contact your estate agent at your earliest opportunity. Don;t feel a wally. Gas boilers are tricky buggers at best, which is why only Corgi registered engineers are allowed to touch them, and you HAVE to have hot water.

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Writer`s Release

This item was edited on Thursday, 24th May 2012, 23:40

Thanks Pete, that was kind of what I thought...wouldn`t be so bad, but we haven`t had a bath for 18 months (had showers obviously, but thats not the same) and I was so looking forward to one last night!

No fluff, mum wasn`t right - that`s not the gas - and it`s not air.  You`ve switchd the mains water on into the sealed boiler system.  That `tap` is to top up the system if the pressure gets low.  What does the gauge indicate?  You need to get the pressure down to around 1-1.2 bar.  You can do that by bleeding a radiator (I`d have the thermostats all open fully to ensure the pressure`s all equal in the system) and in a minute or two it will get down.  You will need one of those small square ended keys to bleed the system and lower the pressure.  You could do it at every radiator also - to make sure there`s no air at the top of any radiator because it`s been off for a while.
The boiler will have an expansion tank that has a rubber diaphragm - hopefully the pressure didn`t get so high as to rupture it.
Once done, if you turn a hot tap on, do you hear the boiler come on?  (it is switched on at the mains isn`t it?)

Ste

No help on your problem. But, its no longer Corgi engineers need to be registered with. Its Gas Safe. If they are still showing they are Corgi send them packing.



"Talking`s for lesbians" Psycho Paul 2011.

Well, the little man finally came this morning, did somethin odd in the boiler cupboard and issued a gas saftey certificate, took him about an hour and he left us with hot water, and to save my gas, he`d left the plug in the bath while running the hot through to check things over...He left us with a bath full of water and hot water running :) 

However, ten minutes later, once the kids were ready for their bath, the plug hadn`t been pushed in all the way and the water had run away, and apparently we no longer have hot water.  The boiler is on and has a warning light flashing on the low pressure, phone little man back and he tells me to turn that funny tap which as SJ rightly said does something to do with the pressure and its stopped working, so although I have water in the taps, that particular pipe isn`t working and I still have no hot water. The little man assures me he`ll be back today :/

I`ve had no bath for the past 18 months...now I have a flash jacuzzi bath and shower and I can`t use either without faffing about with kettles...its incredibly frustrating!

Most combi`s have auto air bleed systems and can quite possibly have just "settled" tho i`d say it was unlikely, as SJ i think said it was the filling loop you had turned on not the gas - the guage is usually around 1 to 1.5 bar for pressure any less the boiler will not run - though you will get water from the hot tap it will just be cold.

If its been re pressurised by mr heating man and has lost pressure again after a few hours you are probably looking at either a small by pass leak in whats called the PRV (pressure reilef valve) which is quite common (have a look outside at the vent pipe and see if you can see signs of fresh water), a small water leak from a rad which will result in lost pressure also - and no hot water - more serious (cost wise) is if the expansion vessel has failed - its job is to "absorb" if you like any expansion in the system as the temp of the hot water rise, its usually a tank at the back of the boiler inside which is a rubber bladder filled with some air that the expanding water presses against - returning back when the water cools down - if thats failed then any pressure rise will result in the PRV venting to the outside world and when your boiler cools down your pressure will have dissapeared and so will your hot water.

Fortunately for you its down to your landlord to fix  

I know the above won`t help you as such but at least you might get an idea of whats going on  

P.S Caveat to the above is it could be several other things but they are the likely suspects...

Grumpy

This item was edited on Monday, 28th May 2012, 14:52

Well, the plumber man came back and topped up the pressure again and seems to think that there is a leak somewhere under my conrete bedroom floor because it is apparently an ongoing problem...suddenly I`m very glad I rent!  This would explain the damp which was covered up when we came to see it, but became apparent when we were decorating, but the pressure hasn`t dropped again, so I`m gonna blame the second drop in pressure on connecting up the washing machine, although I`ve been assured that can`t have caused it.  We now have hot water and my bath is fantastic :)

Thanks for all the advice guys!  I hate moving :)

Well, just a quick update in case anyone is interested, all was going well unil the awful weather hit yesterday and the lack of double glazing made the front room really cold, so we put the heating on for half hour...big mistake...the pressure on the boiler has now dropped out 5 times since then, so the plubmer was back out this morning and is fairly certain there is a leak under my bedroom floor.  He`s gone off now to speak to the landlord and give him his options...apparently they can either inject some stuff into the system which might possibly work, or it`ll be ripping up my bedroom floor and repiping the whole flat...I`m hoping he goes for the injector stuff :/

well i hope if its the latter, the landlord will be moving you at his cost whilst work is done and then compensating you with a nice healthy discount, or perhaps a couple of months free rent?

This item was edited on Wednesday, 6th June 2012, 13:50