The water heater pressure relief valve is a very difficult creature to manage. On the one hand, it is often an annoying little piece of piping that drips onto the floor. It has been noted time and time again that people don't really understand what this little valve is doing, and it can sometimes be taped over or removed, leaving the water heater without any means of relieving the pressure inside. If you have a water heater pressure relief valve, it is vital that you don't touch the valve in any way that will block or break it. The pressure valve can suffer from a lot of problems, but you can get the answers to your queries here.
1. Pressure Valve is Leaking
Water dripping from your pressure relief valve is a good sign, it means that the valve is working properly, and your heater is not overheating. Water heaters can explode if the pressure is not relieved, so if there is water leaking, then it means that the pressure in your tank is exceeding the point where it can be relieved. Try and reduce the pressure by reducing the thermostat.
If you find that the valve leaks on a regular basis then you may find that the problem is a defective valve. Older valves can sometimes be weak due to the extent of time upon the water. Releasing small amounts of water can indicate that the valve has a blockage which is preventing it from closing properly, or even that the valve itself is damaged. In order to avoid this problem, keep your valve clean.
2. Pressure Valve is Noisy
If your valve is keeping you awake at night by making a high, whistling noise, this means that steam is escaping out into the atmosphere, and your boiler may be under too much pressure. A rattling noise when the boiler is working may be caused by corrosion in the valve. If you find that this is the case, then you will need to either clean the valve using a pipe cleaner, or replace it entirely.
3. Valve is Broken
As with malfunction due to water exposure, age and water pressure can sometimes cause the metal of the valve to weaken and split. One example of this is a water valve which is loosened from the heater, and is hanging down. You may find that it is broken off completely, and only hanging on through caulking or other applications. You should check the pipe for this, and replace it if necessary. A valve which leaks water down the heater, rather than dripping it through the valve, might indicate that the valve pipe itself is broken inside.
If you find that you have other problems with your valve, then you will need to call in a professional. Repairing the valve correctly is vital, and if you miss a blockage or other hindrance, then you may be putting your home and family at risk.