Leak in System All aspects of plumbing questions and answers, help, tips and information

[paulb]

Hi All

Hope someone can help, I continually have to bleed 1st radiator so suspect there is a leak somewhere.

There are 13 rads downstairs all in concrete floor no signs of water leaks on ceilng from upstairs rads (under floorboards). How do I find and fix leak without digging up all down stairs floors

Thanks for any help

[htg engineer]

How much of a leak, what radiator ?

If it's always the same one radiator, then check the radiator,valves and piepwork to that radiator (if possible) for small leaks.

If it's only losing tiny amounts of water, and as a last resort - add leak sealer to the system.


htg

[rosebery]

Just because you have to bleed a radiator it doesn't mean you have a leak.

If you have air in the radiator it gets there by one of two means normally.

1. The boiler is turned up to high and is actually boiling the water thus releasing air which will find its way to a high point in the system - normally a rad.

2. Your system is sludged up and the chemical reactions going on are releasing hydrogen which also fids its way to a high point.

What makes you think you have a leak - particularly as you can find no evidence of one? Do you have a combi boiler? If so is it losing pressure all the time? Now thats indicative of a leak.

Cheers

[plumbbob]

I am not quite sure why you would think a radiator that needs bleeding regularly indicates a leak somewhere. OK, it can happen, but it is extremely unusual.

Far more likely, air is being drawn down the expansion pipe into the system and particularly in to the first rad. Classic symptom.

[htg engineer]

What type of system do you have ?

I agree it's not only a leak that would cause the radiator to continually need bleeding - but it can be the cause. So in my opinion it's still worth checking for a leak.

Even though there's no signs of a leak - doesn't mean there isn't one. I've been to jobs where the pressure on a combi has dropped every few weeks and every few months - neither showed any signs on the ceiling, but both leaks were under the floorboards upstairs - and didn't mark the ceiling below.

htg

[paulb]

Thanks for all replies

Radiator is the first in the system,

Boiler is external oil fired,water tank in loft

Thermostat setting is OK

There is a water pressure gauge fitted to boiler

Any ideas on how to progress

Thanks

[htg engineer]

Are you losing system pressure ?

htg

[rosebery]

Just another thought. Is the pump on the flow or the return? If on the return then its sucking the water round and the water in the pipework will be at negative pressure compared with the outside. If you have microleaks in your joints air will be drawn in due to the pressure differential. This has to go somewhere. Not that comon but its a possibility.

Cheers