Boiler help please

[beaufighter]

Can anyone out there with plumbing experience help with a problem please. A couple of years ago I had a new heating system installed and a Glow worm 30ci put into the loft. Not particuarly happy with the boiler as it has had to have a new expansion vessel within its first year as it kept going out. However, this has been cured and although te boiler stays on the performance seems poor. Heating the rads is ok but to get piping hot water out of it just doesn't happen. I appreciate that as it is fitted into the loft there is a delay in the hot water reaching the downstairs taps but unless the tap is only slightly on the water is luke warm. Even using the shower I have the mixer fully on hot which in theory should shut off the cold supply, and it is still not hot enough. There are two controls on the front to adjust the tempature which I have put to max but performance is still poor. I am sure that it was not this bad when it first went in but cannot accept that after two years use it should deteriorate to this extent.

My thought is that there may be something inside that needs to be tweaked. Any ideas please.

[pops]

does the manufacturer have a website you can call up for advise as you say its only couple years old should still be servicable

[POPEYE]

Your right! it should last a lot longer than two years, my old worster was still going strong after nearly 15 years, Several points come to mind,
1. loft is not a good place to site a boiler, too cold, did they fit a frost stat to it?
2. did they lag the pipework properly?
3.i take it it's a combi? the changeover valve could be sticking, the domestic water side of the exchanger could have scaled up which will slow the flow down and effect the water temp, flueing needs checking and burner for carbon build up, easy way to check this if you can see the burner working is, the flame should be blue, if its orange its sooted up,
If its no longer in warranty you need to get it serviced by either british gas or a reputable service engineer that some one can reccomend,
What about the firm that fitted ? phoned them? Good luck

[BUSHWHACKER]

Another way of getting hotter water ouput from a combi is to reduce the pressure of the cold water going into it.

[beaufighter]

Thanks very much for the replies. The flame is blue so I guess the burn is ok. All of the pipes are lagged but I am not sure about the frost stat. What does this look like please? With regards to the changeover valve, I have something in the airing cubboard that I think is a motorised valve as this sounds like a small motor running for a second or two, like a whooshing noise and a positive click would best describe it. I remember the installer of the system changing this as the old one was at fault.

The water pressure may be too high as when I turn the taps off there is a loud bang in the pipes. The manufacturer has not been too helpful in the past as they originally sent an engineer out within the warrenty period as it kept going out who said that there was nothing wrong with it. then, once the warrenty period had expired I contacted them and they sent the same engineer out to cure this ongoing problem and he diagnosed the expansion vessel. I ended up in a dispute, which I won, that this should have been diagnosed and repaired within the warrenty period. Still I shall certainly look for the website.

Thanks again for your help. Aprreaciated.

[Vagrant No2]

My mate had a similar problem . It was the flow pressure valve on the boiler had not been adjusted properley . Once adjusted as per manual , it was then very hot .

[beaufighter]

My mate had a similar problem . It was the flow pressure valve on the boiler had not been adjusted properley . Once adjusted as per manual , it was then very hot .

Thanks for this I will see if this helps. The boiler shows 1.1 bar which I am told is the operating pressure, does this mean the flow is ok?

[BUSHWHACKER]

Thanks for this I will see if this helps. The boiler shows 1.1 bar which I am told is the operating pressure, does this mean the flow is ok?

All the combi boilers I've seen when working in different houses mine included, the operating pressure was always 2 bar.

N.B. this is the central heating pressure and not the water pressure.



With yours Sean, try turning down the valve/stopcock a little to reduce the water pressure of the house/inlet on the boiler.

[beaufighter]

All the combi boilers I've seen when working in different houses mine included, the operating pressure was always 2 bar.

N.B. this is the central heating pressure and not the water pressure.



With yours Sean, try turning down the valve/stopcock a little to reduce the water pressure of the house/inlet on the boiler.

Thanks Vince, I will turn the pressure down as if nothing else it will stop the annoying banging. The pressure I am taking from the display on the boiler. if I open the tap on the boiler I can raise the pressure ok but if it goes too high then it starts to drip slightly from underneath and then goes into a waterfall from the overflow outside the house. Pressure always returns to 1.1 though.

Appreciate your help.

[POPEYE]

Thats the pressure release comeing in, I would never run it above 1.5 bar cold, as it will go up to just over 2 bar when its on, this is plenty of pressure and anything above that is really putting a strain in joints and pipework within the boiler, i run mine on 1 bar and thats plenty, this pressure gauge shows the water pressure within the heating system (rad's etc) and is nothing to do with the tap hot water, the banging sound is more likely air trapped in a capped off spur or a loose (unclipped ) pipe, a bugger to find sometimes, As Vince says you can reduce the cold going in which will slow the flow and give the exchanger the chance to heat it mors but this should be regulated in the boiler itself, could be this regulator at fault, gas valve not lifting suficenty on "hot water called for", circuit board problem, so many things,
Is the flow from the hot taps OK (all of em)? not slow?
Does it get hotter if you turn the tap down a bit?

[beaufighter]

Thats the pressure release comeing in, I would never run it above 1.5 bar cold, as it will go up to just over 2 bar when its on, this is plenty of pressure and anything above that is really putting a strain in joints and pipework within the boiler, i run mine on 1 bar and thats plenty, this pressure gauge shows the water pressure within the heating system (rad's etc) and is nothing to do with the tap hot water, the banging sound is more likely air trapped in a capped off spur or a loose (unclipped ) pipe, a bugger to find sometimes, As Vince says you can reduce the cold going in which will slow the flow and give the exchanger the chance to heat it mors but this should be regulated in the boiler itself, could be this regulator at fault, gas valve not lifting suficenty on "hot water called for", circuit board problem, so many things,
Is the flow from the hot taps OK (all of em)? not slow?
Does it get hotter if you turn the tap down a bit?

Thanks for the reply. Yes, the water flow from the hot taps is fine and is at mains pressure. If I reduce the flow from the tap the water gets hotter but to get anything near to reasonably "hot" the water flow has to be turned to just over a trickle. As I said it was ok when first installed but has deteriorated within the last 8 months or so. Not really noticable durin gthe summer months as I assume that the boiler is not having to work as hard as it is now. I'll try the manual adjustments and see if this has any affect but failing that it may be circuit boards. It just seems so noticable as my mum has just had a similar boiler but a Potterton installed and the performance is fantastic with this. I cannot use just the hot tap to wash hands for example and have to add cold as it is so hot.

Thanks again for help.

[Tallyman]

Have you tried getting someone to open a hot tap whilst you watch the burners. On a demand system the burners should come on full when the hot tap is opened. It could be the pressure switch isn't operating so that the hot water demand isn't being met.

[beaufighter]

Have you tried getting someone to open a hot tap whilst you watch the burners. On a demand system the burners should come on full when the hot tap is opened. It could be the pressure switch isn't operating so that the hot water demand isn't being met.

Just tried this and yes the flame increases when demand is put on.

Thanks for your help.