Boiler help please - i'm freezing!

steinooo

steinooo

steinooo

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Joined
31 Dec 2003
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Stoke on Trent
My Ravenheat 820/20 boiler is hissing and blowing air from the top when I turn the heating on!

The Pressure is on ZERO and has been for a few weeks but the heating has been working, now the hissing noise and clanging in the boiler is too scary to leave the heating turned on. Even though I suspect it will work.

Do I need to fill the water system up? If so I must have knocked off the tap, I cant see how to fill it up, can you tell from this pic what I'd have to do? :

dscn2730u.jpg


I've tried turning the bottom frontmost nut with some pliers and nothing happened.

all help appreciated, I'm freezing cold! thanks in advance.
 
The slotted screw on the brass coloured valve is the tap turn it with a screw driver 1/2 a turn then turn it back when the boiler has reached 1 bar. This may happen very quickly so be ready to turn it off Then run the heating for an hour and then bleed the rads.

Do not turn the nuts on the end of the valve

Disclaimer i aint a plumber
 
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Thanks very much guys, I've just filled it up to 1 bar and turned it on and it hasn't immediately hissed and clanked at me as if it was going to blow up....so so far so good.

Do you think the noises were because I rand it on zero pressure for ages?
 
I think you've been running it with virtually no water in it. Keep an eye on the pressure gauge in case it goes down again. My neighbour had the pressure go down repeatedly in their system and it was because there was a water leak under the floorboards.
 
PapaLazaru said:
I think you are lucky it did not blow up.
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oops :( It didn't sound healthy at all, it's a terrible boiler.

Thanks for the tip monkeygremlin, I certainly will keep an eye on it. Thinking of bleeding some of the radiators soon and I'll check it again after that. The pressure went up a few notches after I turned it on which I expected.
 
You want to worry about where the water has gone though mate... i'd keep an eye on the pressure.. if it drops quite fast you want to go searching for leaks.
 
Yea it's weird there must be a leak somewhere I had a plumber out not so long ago to service it and he couldn't find a leak near the boiler so it must be in the house somewhere :( it doesnt go down quick though I've had this before it takes a month or so
 
anyone got any ideas please - in the last few weeks the pressure keeps going up to 3 bar even when I bleed the radiators to get it down to 1?

I think this is what's causing an overflow pipe outside to start dripping

also one of my radiators is leaking....
 
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steinooo said:
anyone got any ideas please - in the last few weeks the pressure keeps going up to 3 bar even when I bleed the radiators to get it down to 1?

I think this is what's causing an overflow pipe outside to start dripping

also one of my radiators is leaking....
Click to expand...

You have a leaking radiator get it replaced or repaired.
 
do you think that's what could be causing the pressure to go up on the boiler dial?

If so, I could be running into problems by bleeding so much water out?
 
steinooo said:
do you think that's what could be causing the pressure to go up on the boiler dial?

If so, I could be running into problems by bleeding so much water out?
Click to expand...

I'm not 100% sure. There could be air locks which need venting.(beyond the radiators)

You may as well start with the rad. and see how things are from there.

Also once the system is water tight again you're going to want to fully drain and add some inhibitor to the water.
 
Sounds to me that you have fault with your expansion vessel if the pressure is rising when you turn the heating on. The outside pipe will be from the pressure release valve which opens at around 3bar to allow the excess pressure to escape.

The expansion vessel may just need the air pressure brought back up to around 1 bar or the diaphram has perished which means you need to replace the whole vessel.
 
Ours used to do that, had to put the pressure up every other day.

Till my dad, the tight git, finally got a new boiler system in!
 
The bottom fitting in your pic that you tried rotating the nut on is a check valve - one way valve to stop water from the heating loop flowing back into the fresh water pipes.

Dangerous Dave said:
Sounds to me that you have fault with your expansion vessel if the pressure is rising when you turn the heating on. The outside pipe will be from the pressure release valve which opens at around 3bar to allow the excess pressure to escape.

The expansion vessel may just need the air pressure brought back up to around 1 bar or the diaphram has perished which means you need to replace the whole vessel.
Click to expand...
Yep, symptoms match this. Bring the system up to say 1 bar while cold then turn on the heating. Does the pressure increase significantly?

Check the info printed on the expansion vessel. Mine for example states 30psi/2bar. Oh and you have to depressurise the system before checking/repressurising the expansion vessel.
 
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