Was repressurising it when the phone rang, got distracted and the next thing I knew a loud hissing sound was coming from the boiler.
Now it doesn't appear to hold pressure and won't ignite. I would have assumed it would have some kind of blow off valve for exactly the kind of owner idiocy I've just demonstrated.
Or am I wrong and is it now completely knackered?
ta
I'm no expert, but did something similar with mine a few yrs back in my old house.
There should be an over pressurisation valve which will discharge outside or down the drain, maybe the valve has discharged all the pressure, leaving no pressure in the system.
It sounds like the pressure relief valve has stuck open. They usually have a knob you can screw in to drain the system. Wind it in and out a few times and hopefully it'll free off and the spring will push it back into the closed position. Mine was easy to dismantle and service.
Most likely (and I'm no expert), your boiler pressure valve has gone. It needs replacing. Some of them are designed to blow once.
thats what I'd hoped for but now it won't repressurise. An expensive way to start the weekend I feel...
Yep, pressure relief valve stuck open. You might be able to get it closed but if some debris has got in there it may have damaged the seat in which case it will always let by and will need replacing. What boiler is it?
its a vokera linea 24!!!
Whats the blow off valve look like?
It looks just like that. It's fitted with a clip or grub screw (can't remember which) and the outlet pipe screws into the thread. Also, ignore that price. Our company webby always gives retail prices. It'll probably be closer to about £18 iirc.
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nothing that looks like that on my boiler I'm afraid! I have 3 levers, the one for presurising, the yellow one presumably for gas and a wee black square screw valve.
It's up inside the boiler, you'll need to take the bottom cover and the casing off to get at it.
Have a look at pages 26-28, should clear things up a bit.
The discharge from that valve should go outside somewhere adjacent to the boiler.
Turn on the filling loop and see if you can see it coming out of a pipe somewhere probably about 600mm or a metre from the flue.
thanks guys, its reassuring to know there are plenty of folkout there that are happy to spend their friday nights helping a gormless clown sort out his heating issues!...won't lie however, I'm just going to make things worse if I start messing with it. Assuming its this, then what kind of price are we talking about to get someone in to fix it that knows what they are doing. Are we talking hundereds, or is it 50 quid job?
That reminds me of a skydiver whose main chute failed to open, he tried to deploy his reserve but that failed too, as he plummeted to earth he saw a chap flying upwards towards him, as he neared the skydiver called to him - "Do you know anything about parachutes?" The other guy responded "No. Do you know anything about gas boilers?"
😀 IGMC
It'll take someone about 15 minutes tops to change that. You'll still get charged a full hour though that's how plumbers work, add on another £20 for the part and I'd say you'll be looking at £60-70.
Be aware though that sometimes when you over pressure a boiler it can send other things in there haywire as well. Pressure Gauge, Expansion Vessel are two of the things that could have gone.
15 mins for a PRV that is probably buried in the back of the boiler, which in turn is either buried in a cupboard or tight in a corner etc.....
They can be a pain to change (Worcester spring to mind....)
Thanks folks
I think i've got a 'flat fee to fix' deal with scottish gas for 100 quid or so. Might just bite the bullet if its possibly not just the valve thats jiggered and save some money in the long run.
Be aware though that sometimes when you over pressure a boiler it can send other things in there haywire as well. Pressure Gauge, Expansion Vessel are two of the things that could have gone.
You're really sounding like a heating engineer now. 😉 Don't frighten the poor man, if he's not standing in a puddle of water it'll be fine once there's pressure back in the system.
[i]Assuming its this, then what kind of price are we talking about to get someone in to fix it that knows what they are doing[/i]
/strokes chin
"ooooh, it's going to cost you guvna. I can do it for a grand, will next Thursday be OK?"
Haha, I'm just prepping him for the worst. Not an engineer though I just sell the bits, just saying what I've heard from the guys I speak to day in day out at work. If I had my gas tickets I'd have bought the Rocket frame I want by now 😉