Many people contact leak detection companies to come out and find a leak in their house.
When asked what evidence they have that they have a leak, we are often told that there is dampness or a damp musty smell.
In order to keep their costs down we would advise them to get a plumber to carry out the following tests to prove if they have a leak on their pipeline.
1 – Turn off the mains water supply to the storage tank in the attic and put a pressure gauge on the incoming mains water.
2 – Put a pressure gauge on the outlet of the hot water cylinder and turn off the supply to the cylinder.
3 – Install a pressure gauge on the heating system and turn off the top up to the heating.
Keep the test on for say, twenty four hours. Do not use any water out of the pipe lines that you are testing as this will make the test pointless. If any of the above pressure tests drop then it is very likely that there is a leak on it.
The first 2 are fairly straight forward if you find that they are leaking as the only option you have left is to get a leak detection company to narrow it down.
A leak on the central heating system is a lot trickier and harder to narrow down.
This is due to the larger distance in pipework and the system being being heated up so that the leak may not be as bad when the heating is on as the pipework will expand and close down the hole that the water is escaping through. However a plumber can still help you out here.
If it is possible the plumber could install gate valves on the system to separate it into zones and pressure test each zone on its own to narrow it down further.
There is also the pipes leading out to the boiler and back again that could be leaking, these can also have valves fitted and be pressure tested.
One part that many people overlook and is not so rare to happen, is that in the copper cylinder there is a coil of central heating pipe that can leak. This can be tested by valving it off and testing the rest of the heating system. If it holds pressure then the leak is on the coil in the cylinder.
If none of the above tests show any drop in pressure then the problem of the dampness is not due to a leaking pipe. We would suggest you contact a good building contractor to inspect the roof, windows and damp proof courses.