Leaking water tank
If you think your water tank is leaking, before you take any action you’ll need to be sure that water isn’t coming from an adjacent pipe. It’s also possible that condensation could be dripping down from the side of the tank or connected pipes, leaving a suspicious pool of water near the tank.
To diagnose a leaking water tank follow these three steps:
Turn off your gas central heating
Once the system has had a couple of hours to cool down, check and see if there’s still evidence of a leak, such as a pool of water, or water dripping down the side of the tank.
Check the temperature pressure relief valve (TPV)
Located at the top of your boiler ensure the temperature pressure relief valve is tight, but not too tight.
Check the seams of your water tank
Look for signs of corrosion such as rust. If you find any it’s likely you’ll need to replace the tank.