HOME > Mechanicals > Pipe, Valves, Fittings > Valves > Water Valves

Pressure Regulator Valves

Water is delivered under pressure, but that pressure varies depending on location and the conditions under which it is delivered. It also varies with temperature; as the temperature rises, pressure increases. This pressure must be controlled for safety reasons, but also to provide a reliable rate of flow.

Pressure Reducer Valve

The pressure reducer is the second valve found inside the home. It's the first valve after the main shut-off valve.

When the supply main pressure exceeds 60 psi, an approved water pressure reducing valve and strainer should be installed in the water service pipe near its entrance to the building to reduce water pressure to 50 psi or lower.

Sillcocks and outside wall hydrants may be left on full main pressure at the option of the owner.

The pressure reducing valve is spring-loaded. It remains open until the pressure in the building reaches a set level. Then it closes and remains closed until the pressure in the building begins to drop.

It typically is bronze with a union inlet connection. It is installed when the water pressure in the incoming line exceeds 60 psi, and can handle incoming pressure up to 300 psi, and reduce it to an outlet pressure of approximately 50 psi, but this is adjustable.

Pressure Relief Valve

A pressure relief valve is a safety device on a water heater or boiler or pressure tank.

When the pressure in the system builds to the point of being unsafe, the valve opens and allows steam or water to escape. Without this safety device, a tank could explode.

This valve will operate when either the temperature or the pressure becomes too high due to an interruption of the water supply or a faulty thermostat. Its inlet is MIP threaded. Fig. 19

All hot water heaters should be fitted with a temperature-pressure relief valve no matter what fuel is used.

See Also:

Links to Related Websites:

 BACK

Was this article helpful?   Yes    No