Discharge Rates Sheet

a company
®
®
DOCUMENT #: REVISION:
BF-RV DISCHARGE 4/12
SPECIFICATION SUBMITTAL SHEET
Model 375, 375A, 475 & 975
Reduced Pressure Principle &
Reduced Pressure Detector Backow Preventers
WILKINS a Zurn company, 1747 Commerce Way, Paso Robles, CA 93446 Phone:[phone] Fax:[phone]
In Canada: ZURN INDUSTRIES LIMITED, 3544 Nashua Dr., Mississauga, Ontario L4V 1L2 Phone:[phone] Fax:[phone]
Product Support Help Line: 877-BACKFLOW (877-222-5356) • Website: http://www.zurn.com
GENERAL INFORMATION
Reduced Pressure Principle Backow Preventers can and
will discharge water. For indoor installations, pit or vault
installations or protective enclosures, a drain needs to be
provided that can handle the amount of water discharged.
This chart shows the maximum amount of water that can be
discharged from the device based on the line pressure where
it is installed. Rarely will a device discharge this amount of
water, but if it does happen, it can cause ooding, building
damage or a cross-connection that can contaminate the
water supply. Therefore a drain MUST be sized properly.
WILKINS shall not be responsible for damage caused by
the lack of a drain or an undersized drain.
To reduce the risk of water damage due to relief valve
discharge, specify the WILKINS Model 375MS.
For additional information, send for BF-375MS, BF-375AMS
BF-475MS&VMS, BF-475&VMS212&3 and BF-EST.
TYPICAL INSTALLATION
375MS with ZW106 Solenoid Control Valve
and EST Electronic Solenoid Timer
150
100
50
0
200
0 400200 800600
Relief Valve Discharge Rates
Model 375, 475 & 975 RP & RPDA
Backflow Preventers
ZONE PRESSURE (U.S. PSIG)
FLOW RATE (U.S. GPM)
1/4-1/2"
3/4-1"
1 1/4-2"
2 1/2-6"
8-10"
(Worst case condition- If 1st check or relief valve is lodged wide open)
Electric
Solenoid
Timer
12" MIN.
30" MAX.