There are four types of valves that are mainly used in plumbing and fitted along both the hot and cold water supplies and these are: gate-valves, drain-valves, stop-valves and servicing valves. They are used in different places along the water supplies and they are designed and work in a slightly different way from each other. Thanks to valves you can switch off certain parts of the water supply in case of a leak or maintenance needs. In this article I will tell you a bit more about stop-valves and also go through some common issues with valves.
The stop-valve can be found where the water pressure is at its highest, normally by the mains pressure and as you can tell by its name, it is also the main stop-valve fitted to the rising main. It works very similar to a normal tap, in the way that it allows the water to flow up through an orifice. The orifice can then be closed by a jumper with a washer screwed on to it. The good thing about stop-valves is that they have small arrows stamped on them, showing which way they should be fitted and they are also normally sold with matching compression fittings. Do check that they have been approved to be fitted to the mains water pipes by the water company before installing any. Stop-valves is not only used in the rising main but can also be fitted in the so called branch pipe in connection to an electric shower or on pipes leading to a dishwasher, washing machine, a water softener or even a garden tap. The latter might need to have a double-check valve fitted as well.
Issues with Valves
A common issue with valves is that the gland packing might need to be replaced once in a while. This is changed in the same way as you would change it on a tap. A good thing though is that the washer rarely needs to be replaced. One of the main issues with valves and especially with stop-valves is that they can get stuck when open. It is therefore advisable to open and close these valves on a regular basis to prevent them from getting all ‘gummed up’. If they get stuck, try applying some penetrating oil until they get unstuck. Be careful not to force them open as this might damage the valve itself. Once you have gotten the stop-valve unstuck, open it completely and then partly close it, about 1/2 to ¼ a turn should do it. Do not worry about the water flow as it will hardly be affected by this but it should hopefully prevent the stop-valve from getting stuck when being used in the future. Luckily this is not an issue with balltype servicing valves and gate-valves.