Is anyone handy with a gas boiler?

Scuzi

Scuzi

Scuzi

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I have a gas boiler to supply my heating and hot water. According to the manual, the ideal system pressure is 1.0 bar but it has been hovering around 0.7-0.8 bar for a while which is within the safe limits.

Tonight I bled the radiators and the system pressure has fallen to 0.4 bar and as a result the boiler won't fire up. It needs to be at least 0.7 bar to work.

There is a tap underneath the boiler to pressurise the system but when I turn it nothing happens. It doesn't feel or sound like any water is flowing and the pressure gauge doesn't move.

Can anyone suggest why it won't pressurise? I need hot water for a shower in the morning and as it stands I'm screwed!

Thanks :)
 
Urm with the one we had in our last house and the current one we we're told to try and keep it around 1.5 other wise it wouldnt really like it (more than 2 though would be explosion time)

Id leave it off for half an hour then turn it on with the heating and run a hot tap for a little bit and get some water running through it (though hopefully someone more qualified could give some advice as im only a lazy student)
 
LACKERKNACKER said:
They'll be another tap you need to turn on.
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I've had a mosey for another tap but can't find one anywhere :confused:



pingwing said:
Urm with the one we had in our last house and the current one we we're told to try and keep it around 1.5 other wise it wouldnt really like it (more than 2 though would be explosion time)

Id leave it off for half an hour then turn it on with the heating and run a hot tap for a little bit and get some water running through it (though hopefully someone more qualified could give some advice as im only a lazy student)
Click to expand...
I'll give that a try and report back.

Thanks guys.
 
Our one has three taps. One which is the first port of call, and then two others (next to each other) of which you only need to do one.
 
We have had a few combi boilers over the years and yes when the pressure drops below 0.4 they tend to shut off as a safety precaution.

To top up and pressurise the system sometimes there is a Tap and or a screw to let water in like the one below

http://www.wickes.co.uk/Straight-Filling-Loop/invt/160094

We have had a couple of the tap ones break :( when they go they will not let water in.

We now have the screw sort that has 2 screws that have to be opened.

Has you tap system also got a screw valve ?

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what make of boiler is it? i had exactly the same thing happen, i couldn't find where the flaming tap was to refill the boiler so i had to get my mate round to sort it out. the tap was really small, just a bit of black hard plastic, no bigger than a 2p and it was easy to miss.
 
You sure that's the right tap to be turning?

We've got a Gas boiler (not combi or anything) that does the central heating and the hot water tank, it's a sealed/pressurized system and to up the pressure we turn a tap up in the loft that's by the expansion vessel (red tank looking thing with a diaphragm inside).
 
look below the boiler, if its wallhung.

There should be a "filling loop", its usually a flexi hose, this connects between the cold water supply and the heating circuit.

It shouldnt be left connected, so maybe thats why youre struggling.

Al
 
Westyfield2 said:
You sure that's the right tap to be turning?

We've got a Gas boiler (not combi or anything) that does the central heating and the hot water tank, it's a sealed/pressurized system and to up the pressure we turn a tap up in the loft that's by the expansion vessel (red tank looking thing with a diaphragm inside).
Click to expand...

different type of system you have there compared to op's

a combi boiler has the filling link attached to it

if it is a braided filling link like the one in the link then chances are the link is isolated on both sides turn the black tap on and then check the other side of the link (trace the braided hose back it's 300mm long) you should find an isolation valve that will take a flat headed screwdriver turn that either way until you hear the water run fill it to approx 1-1.5 bar and all will be fine you may have to reset the boiler before it comes back to life.

If you have a worcester boiler things may be a bit different as they use a key to fill the system
 
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It sounds like you have to purge the system, you "need" to have a corgi registered guy to do it, but ive purged mine a few times myself. Turn the boiler off 1st and open a window, then find which pipe carries the gas, where that connects to the boiler there should be a large nut you can loosen slightly. If you paint some soapy water over the pipe and nut, bubbles will appear when the air is flowing through. Have a sniff for gas and as soon as you can smell it tighten the nut back and try the pressure valve again.
 
Bennie-Mac said:
It sounds like you have to purge the system, you "need" to have a corgi registered guy to do it, but ive purged mine a few times myself. Turn the boiler off 1st and open a window, then find which pipe carries the gas, where that connects to the boiler there should be a large nut you can loosen slightly. If you paint some soapy water over the pipe and nut, bubbles will appear when the air is flowing through. Have a sniff for gas and as soon as you can smell it tighten the nut back and try the pressure valve again.
Click to expand...

good post but the op states 0.4bar water pressure the boiler has locked out due to this not gas pressure
 
Bennie-Mac said:
It sounds like you have to purge the system, you "need" to have a corgi registered guy to do it, but ive purged mine a few times myself. Turn the boiler off 1st and open a window, then find which pipe carries the gas, where that connects to the boiler there should be a large nut you can loosen slightly. If you paint some soapy water over the pipe and nut, bubbles will appear when the air is flowing through. Have a sniff for gas and as soon as you can smell it tighten the nut back and try the pressure valve again.
Click to expand...

You are seriously beginning to worry me mate!.
 
Having watched the video in the link a few posts above it appears that I don't have a filling loop. The guy in the video said by law it is supposed to be disconnected so I assume that is the case with mine. I can't find one though...surely there should be one with the boiler?
 
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