You may not know exactly how your hot water system works, but you know that its cylinder is there to hold water. If you see a leak coming out of the cylinder's valve, then you may worry that something is wrong. Is it normal for this valve to leak, or do you need to call an emergency plumber?

Occasional Leaks

It's normal for the valve on your hot water cylinder to leak every now and then. This usually happens when the water is heating up. These leaks are more likely to be occasional drips caused by the pressure of cold water turning hot and expanding. They don't last long.

So, if all you see is the occasional drip when your hot water heats up, then you shouldn't worry. If the leak doesn't stop after a while or if it happens at other times, however, then you may have cause for concern.

Constant Leaks

Sometimes, hot water cylinders don't just leak when your hot water is heating but leak at times when you aren't using hot water or haven't used any for a while. Sometimes, the valve leaks constantly. This can be anything from a drip to a real leak. If you're losing a lot of water, then your hot water pressure may drop, or you may not have as much hot water as usual.

This kind of leak is more serious. It implies that you have a problem with the valve itself. For example, valves can be affected by calcium deposits that build up in the hot water cylinder. Calcium can gum up the valve or block its pipes and stop it from working correctly.

If you have an older cylinder, then you may have corrosion on or in the valve. In either case, your valve needs to be cleaned out, repaired or replaced.

If you're seeing anything other than a regular occasional drip, then you need to call your plumber as an emergency. Valves on hot water cylinders are there as a safety measure. If the valve is failing, your system isn't as safe as it should be. Plus, if any damage gets worse, then your whole system could be affected.

Call your emergency plumber and tell them about your leak. They can work out how quickly you need a call-out based on their assessment of the problem. If there is a delay, they can advise you on how to deal with the cylinder until they get to you.