Hale RSD - Manual (Page 23)

23 Section 2a: Accessories
Hale Products, Inc., Nov. 2005, Rev-A
Ac ce ss or ies
❑
The P Series relief valve system is a bronze, variable-pressure setting, relief
valve that prevents undue pressure per the requirements of NFPA Standard
1901. An AMBER indicator light on the operator control panel signals when
the valve is open. (See Figure 2a-2: “P Series Relief Valve System
Arrangement,” on page 22.)
The P series relief valve system consists of a panel mounted control valve
(PM) and a P25, P30 or P30V relief valve. The valve is mounted in the dis-
charge piping and plumbed back to the pump suction. Valve connections
are either flanged or Victaulic
™ .
Thermal Relief Valves (TRV)
Figure 2a-3: Thermal Relief Valve, TRV