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https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl DIY Forum >> Plumbing Questions >> Leak Detection https://www.askthetrades.co.uk/cgi-bin/yabb/YaBB.pl?num=1319816665 Message started by DB on Oct 28^th, 2011, 4:44pm

Title: Leak Detection
Post by DB on Oct 28^th, 2011, 4:44pm

Hi,

My boiler keeps losing pressure rapidly. I put it up to 2.5 bar and witin 2 hrs it had gone down to 0. When I top it up and turn the central heating in it loses 25% immediately and the decreases until it gets to 0. I've had a couple of plumbers in who have checked the boiler over and suggested it's a leak (there's nothing wrong with the boiler). Problem is I've got wood on the first floor- where we're sure the leak is. It's a suspended floor- wood on chipboard, then the pipes. So, the only way to get to the pipes is through the floor- which will prove costly. One plumber put leak sealer oin the system, which didn't work.
I checked the rads for leaks, by turning the central heating up. Found nothing, but one of the rads didn't heat up- should I make the assumption the leak is on a pipe connected to this?

I've seen a company which uses specialist equipment to find the leak and fix it- minimising damage to the floor (www.adileakdetection.co.uk). Has anyone got any experiance using a company like this? It would really kill me to shell out for this and have to rip the floor up anywyaa!

Any advice would really be gratefully received

Many Thanks

Title: Re: Leak Detection
Post by CWatters on Oct 28^th, 2011, 5:41pm

Did they check for water coming out of the PRV valve? Best way to do that is to put a plastic bag under it or divert the output to a dry bucket. Then pressurise the system, turn the heating on and see if any appears in the bag/bucket.

Title: Re: Leak Detection
Post by DB on Oct 28^th, 2011, 6:17pm

Thanks for the reply- I'm a complete numpty when it comes to plumbing/ boilers- where can i find the prv valve? It's a potterton gold...

Cheers

Title: Re: Leak Detection
Post by Lectrician on Oct 28^th, 2011, 7:35pm

A copper pipe sticking out through the wall, usually close to the boiler - it is where hot water would be ditched if the system pressure was exceeded.

Finding a leak can be a PITA, but look at your decor! Stains?

Often, a plumber can isolate the plumbing in half, maybe up and down, and let the system run with just one area on, proving which side the leak lies.

If it is under the upstairs floor, if it can be narrowed down, removing the ceiling below, re-boarding and re-plastering sounds scarey, but is not toooo expensive when you consider lifting your floor!

Perhaps a great excuse to get rid of your artex :P

Title: Re: Leak Detection
Post by thescruff on Oct 29^th, 2011, 9:51am

Information, plus makes and models help.

The boiler pressure should be no more than 1.5bar when cold.

I would guess subject to information the expansion vessel is duff or lost it's pre-charge.

Should be the first thing the plumber checks.

Title: Re: Leak Detection
Post by cumbriahandyman on Oct 29^th, 2011, 12:48pm

As above.

But be aware ADI are expensive...