Cold water expansion valve.
My last blog was on a Hot Water Cylinder relief drain.
Connected to the relief drain is a cold water expansion valve. This is an energy saving device, generally situated low on the system. It is designed to relieve the pressure that is created when water heats up. The valve operates on a certain pressure and is factory set, due to this no maintenance can be carried out on the valve, however, these very rarely fail. This is the valve that will cause the constant drip via the relief drain, which should be cold water. The valve works in unison with the Temperature and Pressure Relief Valve which I will discuss on my next blog.
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