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Weathermatic 21000CR Series Valve

Weathermatic 21000 series valve
Weathermatic 21000 Series Valve


This is Weathermatic's valve for commercial and high-end residential use.




This is a fairly typical valve designed for general commercial use. Like other Weathermatic valves it has reverse flow porting and a shock cone to reduce (but not eliminate) potential for water hammer. This is a good quality valve, with a glass-filled body that is rated to 150 PSI. The valve has a 5-year warranty. This is a valve I am very comfortable with using on my best client's projects.

The XPR pressure regulator option is used if you have high water pressure and need to reduce it to make the sprinklers or drip system work correctly. This module needs a minimum flow of 10 GPM through the valve. It should also be set so the outlet pressure is at least 10 PSI lower than the water pressure at the valve inlet. I suggest that 15 PSI is a more suitable minimum pressure drop. If the pressure drop is not high enough the valve will not keep the pressure uniform, and you will have large swings in pressure which defeats the purpose of the pressure regulating valve. Therefore if you are using the XPR option I suggest you use a pressure loss of 15 PSI or more for the valve.

This valve is labeled as contamination resistant. It is important to understand what this means. This does NOT mean that the valve can handle really nasty water. What they mean is that it will be able to deal with the small amount of sand that typically comes form well water. If the water looks dirty you should install a separate filter system before the valves.

Manufacturer's Performance Data:

Valve Pressure Loss for 21000CR Series
Flow in GPM 0-4 6 8 10 15 20 25 30 35 40 45 50 55 60 70 80 90 100 110 120 130
PSI Loss for 1" valve 1.2 1.4 1.6 1.7 2.0 3.3 3.0 4.3 6.0 7.7 9.5 11.5                  
PSI Loss for 1 1/2" valve           1.3 1.6 1.9 2.4 3.0 3.8 4.6 5.6 6.7 9.5 13.0          
PSI Loss for 2" valve                   2.3 2.4 2.6 2.7 2.9 3.3 3.4 4.2 5.2 6.7 7.7 8.8