Pressure Reducing Valves are generally used as a control device to prevent over pressure in a water system. People often refer to Pressure Reducing Valves as Pressure limiting Valves or Pressure Governors, in fact all 3 will operate in the same manner but are looked at as 3 different types of valves, however the terms of Pressure Limiting Valve or Pressure Governors are just terminology used by different people and in fact are all just Pressure Reducing Valves.
A Pressure Reducing Valve is referred to as a Drop Tight Valve, this means that once the Pressure Reducing Valve is set it will only allow the desired pressure to pass through. It is recommended that all Pressure Reducing Valves are regularly serviced to ensure the maximum life span for any valve. To service you would remove the cartridge and ensure that the filters are clear of all debris and that there is no damage to the spring inside.
Pressure Reducing Valves work in a very simple manor. They are typically set up with a spring and diaphragm that work against the forces of the inlet water pressure and in turn determine the outlet pressure of the water. When the force of the incoming water increases this in turn increases the load on the diaphragm and increases the spring load, when the water inlet pressure decreases the load on the diaphragm decreases and the spring load in turn acts to keep the Pressure Reducing Valve flowing at the right pressure, this means that if you have a sudden increase or decrease in inlet pressure you should not have any difference in water pressure after the Pressure Reducing Valve.
In some instances you can get water hammer or chattering caused following the installation of a Pressure Reducing Valve, this can be caused where there is a large difference between the incoming pressure and the outlet pressure of the Pressure Reducing Valve. This can be overcome but what is known as staging, this is where you gradually bring the water pressure down by using more than one Pressure Reducing Valve on the system.
At Advanced Water Company we offer a range of Pressure Reducing Valves from many different manufacturers, please see some useful links below.