Plumbers please Glowworm 18sx Question

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Does anyone know how to release pressure from this boiler?
Currently it is sat at around 2 bar, and not firing up. I spoke to a friend of mine who said it should be about 1 bar max. So I googled the manual to see how to release pressure from it, but it doesn't say.

So, does anyone know how to drop the pressure from 2 to 1 bar on this boiler?

Thanks
 
Either drain water out of the radiators from a drain valve or (not all that recommended) undo the pressure release (red valve inside the boiler) until it drops. It should work fine at 2 bar though, almost all boilers are designed to work a 1-2.5 bar.
 
Too much pressure wouldn't cause it not to fire, you have another problem. If the pressure goes over around 3.0-3.5 bar then the Pressure Relief Valve would release it.
 
Yup, the pressure isnt your problem but it is a fraction high. Ideally it should be between 1 and 1.5bar.

As above, there is a red release valve inside the boiler which will be like a medicine cap. Push in and twist. Water will exit via the boiler overflow.
 
Thanks will go and try releasing some and see if it fires up in the morning.

The most annoying thing is, the little display just says "F9" which after googling etc just seems to say "There is something wrong, but we can't tell you what"
 
Thanks will go and try releasing some and see if it fires up in the morning.

The most annoying thing is, the little display just says "F9" which after googling etc just seems to say "There is something wrong, but we can't tell you what"

Assuming you mean Glowworm 18 SXI:

"F9 - Water pressure sensor fault - Faulty sensor connection, check wiring".
 
infact i think F9 on glow worm boilers is a low pressure fault.

have you reset it?
 
Assuming you mean Glowworm 18 SXI:

"F9 - Water pressure sensor fault - Faulty sensor connection, check wiring".

I've literally just found the installer manual and seen that, where would I check this in the boiler?

infact i think F9 on glow worm boilers is a low pressure fault.

have you reset it?
I have to reset it every morning when I get up and let more water (I assume) in from the tapped pipe that leads into the bottom of it to get it to fire up and start heating again.
 
Iuse to have this problem with my old boiler turned out to be the Exhaust sensor needed replacing as it could not detect that the gas exhaust was clear and not blocked up. this would stop the fan from spinning up and would stop the boiler igniting. replaced the sensor and job done.
 
DONT release water out of the PRV! Once opened they dont usually hold water again! And you'll be buying a new PRV. The PRV is a safety device, not a drain point!

Use the proper drain point under the boiler. And yes your specific boiler does have one. :)
EDIT: See page 32 Diagram 12.11

As said above water pressure at 2bar is not the cause of your problem.

By the sounds of things your water pressure switch is doing its job and telling you, your boiler has a problem.

Most likely that the expansion vessel has failed or needs repressurising: Start cold with 1bar, run heating and see how high it goes. Gets to near 3 bar, and thats your problem.

PRV could be continually dripping, go outside and check. If so new PRV time.

Possible system leak, go check round the heating system for wet patches.

I'd advise you to get someone qualified in to look at your gas boiler instead of you going and messing around with your boilers internal components.. Horrible cheap boiler full of plastic rubbish imo :D

Be safe
Mick
 
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.. Snip
Be safe
Mick

Right, too late to read that as I have been flooding the bathroom by draining a radiator and the little screw tap thingy falling out of it! :o Anyway got the pressure down to 1.3 now and after a reset (without adding any more water back in) it has fired up again.

I've looked through the manual (Flexicom_sx_installer_manual.pdf) and the diags that you describe do not appear where you are saying. Page 32 for me is "Flue Preparation and Installation".

Will see how it does in the morning when I wake up.

I agree it's a horrible boiler and the guy I spoke to earlier (works for Transco) said the same thing while shaking his head!

Thanks all so far, will report back in the morning.

Anyone suggested rubbing mustard on the stopcock yet?

I tried that, it washed away when the bathroom flooded :p
 
Is your boiler a flexicom or a 18sxi ?

Drain point for 18sxi:

drainpoint18sxi.jpg


Drain point illustration for a flexicom ( from Glowworms webpage ) is page 53 diagram 15.1

Fexicom range only goes down to 24! So not sure how you have an 18.

Mick

EDIT: Found it ( I think ) you have a Flexicom 18sx, sealed system boiler?? Drain points on page 37 diag 11.1

Even so, get someone in..
 
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Right, too late to read that as I have been flooding the bathroom by draining a radiator and the little screw tap thingy falling out of it! :o Anyway got the pressure down to 1.3 now and after a reset (without adding any more water back in) it has fired up again.

I'd call that fixed and forget about it, modern boilers are a nightmare of badly made parts and cheap electronics. Don't believe what people tell you about different makes being better etc from my experience it's a total lottery I've seen cheap ones run for years with out issue and expensive ones cause nothing but problems.

I never call the boiler man until I've had a good fiddle around and googled my symptoms, you'd be amazed how often you can fix them with a part for a few quid without needing to splash out on the crazy fees some of these people charge. Oh and before anyone chimes in provided you don't work on any of the gas elements of the boiler you are doing nothing wrong even under the most ridiculous interpretations of the law.
 
We have a gloworm boiler and its had every major part replaced at some time since it was installed back in 2006. Absolute nightmare :(

It has killed 3 or 4 sani-blocks with hairline cracks (all the pipes go into it or something?), sensors going bad, wiring faults, air pressure faults, dead timer etc.
 
Just worked on an 18sxi this morning, took a picture of the inside for you. Probably not any help, but I did it anyway :p .



(Note: I forgot to reconnect the earth lead before taking the picture, that's why it's hanging there)
 
Just worked on an 18sxi this morning, took a picture of the inside for you. Probably not any help, but I did it anyway :p .

Thank you very much, for some reason mine looks different. It does seem to be firing up okay at the moment though and the pressure is a 1.0Bar so will see how it gets on over the next couple of days.
It is usually in the morning that it decides that it is not going to work until I fiddle with the reset and the tap.
 
I took the first case (decorative mainly), then the second case off to get it to that stage. It may well be slightly different, but it will be similar (same burner, fan and gas valve/zero governor).

Does the pressure drop to 0 overnight then? And then you're topping it back up?

If so, check that the pressure relief pipe (should go outside, copper) to see if it's dripping water. Don't confuse it with the plastic (white) condensate pipe, that should drip when the boiler is on.

If the copper pipe is dripping then chances are either the pressure relief valve is letting by water or the expansion vessel is flat and needs recharging. The expansion vessel is the red thing on the right of the photo I took and it just has a little cap on it that you unscrew and a schrader valve underneath (like on the tyres of a car or bicycle). Unfortunately you need to remove all of the pressure from the boiler before you pump it up, but if it's dropping to 0 overnight anyway, that won't be a problem! You need to pump it up to about 10psi on most. This can be done using either a foot pump or a hand pump (but then you need to check the pressure with a gauge). Then use the filling loop as usual to put the pressure up to 1 bar and it should keep it!
 
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