Central Heating Leak?

[msheppard36]

Looking for some help please. For some time, my boiler has been losing pressure. If I top the pressure up to 1 bar, it will take about 3-4 hours to drop to 0 bar. Its a combi and this happens with heating and hot water.

I have had a plumber look at it, and he told that as the boiler still provides hot water for taps and heating, there cant be a problem and it must be a faulty gauge.

Im not convinced of this at all. When I turn on my heating, the pressure will rise to about 1.5 bar, then once the heating goes off, it drops to 0 again after a couple of hours.

Ive checked rads, valves and theres no evidence of any leaks, but could the gauge be faulty? I cannot inspect the pipework easily as its all beneath the floors.

My insurance covers this, but wanted a bit of advice before I call them, just in case its an easy fix or it is the gauge.

Thanks.

 

[45yearsagasman]

Your plumber is a waste of space. Call a proper boiler repair man and trust him to find your problem. Your plumber is talking out of his a**e.
Check the pressure relief is not dripping from the discharge pipe outside, and come back.
The gauge is not at fault, but is indicating a fault on your boiler or system.

 

[msheppard36]

Thanks, Ive checked everything that is accessible and the pressure relief valve is not leaking, so I assume its a leak in the pipework somewhere.

Im tempted to try a leak sealer but is that really a long term fix, surely its better to find the cause?

Im wondering, could a leak to a hot tap cause a drop in pressure?

 

[Mike2007]

Thanks, Ive checked everything that is accessible and the pressure relief valve is not leaking, so I assume its a leak in the pipework somewhere.

Im tempted to try a leak sealer but is that really a long term fix, surely its better to find the cause?

Im wondering, could a leak to a hot tap cause a drop in pressure?

Your hot tap and your central heating are on completely different circuits. Has the pressure been good until now or always bad? Has some work been done to the system lately (new rad, rad removed). Has anybody been drilling walls, floor, screwing boards down??

 

[msheppard36]

No work has been done on anything. I noticed the problem about 6 months ago and left it after the plumber told me the gauge was faulty.

When the boiler starts up to maintain hot water, the pipes gurgle and make a right racket, so I need to get this sorted before it starts getting cold.

 

[wiggikins]

Floorboards upski methinks??

 

[Mike2007]

No work has been done on anything. I noticed the problem about 6 months ago and left it after the plumber told me the gauge was faulty.

When the boiler starts up to maintain hot water, the pipes gurgle and make a right racket, so I need to get this sorted before it starts getting cold.

If you pump it back up and you loose pressure you are also loosing some water. You should see this water by now coming through ceiling or around the rads! So it sounds like its on the boiler, expansion vessel gone(big red thing inside) or blow off valve letting by. Is it dripping from that copper pipe that is poking through wall outside?

 

[msheppard36]

Yes, each time I pump it back up, it loses pressure over about 3-4 hours. All pipework is below floorboards (single storey) and theres no evidence of water around rads. I cant see a copper pipe outside anywhere, other than the plastic oil line and there a copper pipe with the fire valve wire going through. The pressure relief pipe goes through under the floor and I cant see one coming through the wall anywhere outside.

 

[Mike2007]

Yes, each time I pump it back up, it loses pressure over about 3-4 hours. All pipework is below floorboards (single storey) and theres no evidence of water around rads. I cant see a copper pipe outside anywhere, other than the plastic oil line and there a copper pipe with the fire valve wire going through. The pressure relief pipe goes through under the floor and I cant see one coming through the wall anywhere outside.

The discharge pipe is a "warning" pipe and should be clearly visable on outside wall behind boiler. If pipework leak it nearly always compression joint that has become loose, unless its damaged pipework. Also pipework that has been covered with mortor/ concrete and gone rotten due to alkaline cement?

 

[msheppard36]

Thanks, my boiler is situated in a cupboard in the house with no outside wall. The flue goes up through the roof, so I cannot see a discharge pipe anywhere.

I'll just bite the bullet and get a plumber in to check everything. If it turns out to be leak somewhere hard to get to, i'll go through my insurance company.

Thanks for the help.

 

[wiggikins]

Floorboards upski methinks??