ANDERSON GREENWOOD
TyPE 95 POSRV
MAINTENANCE INSTRUCTIONS
VALVES & CONTROLS
ANGMC-6026-US-1312
Copyright © 2013 Pentair
The intent of these instructions is to acquaint the user with the maintenance of this product.
Please read these instructions carefully.
Engineering Doc. #05.9040.083 Rev. E
SAFETY PRECAUTIONS
When the pressure relief valve is under
pressure never place any part of your
body near the pilot exhaust nor the outlet
of the main valve.
The main valve outlet should be piped or
vented to a safe location.
Always wear proper safety gear to protect
head, eyes, ears, etc. anytime you are
near pressurized valves.
Never attempt to remove the pressure
relief valve from a system that is
pressurized.
Never make adjustments to or perform
maintenance on the pressure relief valve
while in service unless the valve is isolated
from the system pressure. If not properly
isolated from the system pressure, the
pressure relief valve may inadvertently
open resulting in serious injury.
Remove the pressure relief valve prior to performing any pressure testing of the
system.
The safety of lives and property often depends on the proper operation of the pressure
relief valve. The valve must be maintained according to appropriate instructions and
must be periodically tested and reconditioned to ensure correct function.
WARNING
Removal of the seal wires in an attempt to adjust and/or repair this product by
unauthorized or unqualified persons voids the product warranty and may cause
damage to equipment and serious injury or death to persons.
The product is a safety related component intended for use in critical applications.
The improper application, installation or maintenance of the product or the use of
parts or components not manufactured by Anderson Greenwood may result in a
failure of the product.
Any installation, maintenance, adjustment, test, etc. performed on the Product must
be done in accordance with the requirements of all applicable Anderson Greenwood
Procedures and Instructions as well as applicable National and International Codes
and Standards.
STORAGE AND HANDLING
Pressure relief valve performance may be adversely affected if the valve is stored for
an extended period without proper protection. Rough handling and dirt may damage,
deform, or cause misalignment of valve parts and may alter the pressure setting and
adversely affect valve performance and seat tightness. It is recommended that the
valve be stored in the original shipping container in a warehouse or as a minimum on a
dry surface with a protective covering until installation. Inlet and outlet protectors
should remain in place until the valve is ready to be installed in the system.
1.0 GENERAL VALVE DESCRIPTION (REFER TO FIGURE 1)
The Anderson Greenwood Type 95 Valve consists of a main valve and pilot. The main
valve has an unbalanced piston with O-ring seat. Tank pressure is applied to the top of
the piston by means of the pilot. The area of the top of the piston is larger than the
bottom and the valve remains closed.
When the tank pressure increases to the set pressure of the pilot, the pilot opens and
vents the pressure from the top of the piston. The force acting on the bottom of the
piston is now greater than that acting on the top and the valve opens.
When the tank pressure decreases to the closing pressure of the pilot, the pilot closes
and tank pressure is directed to the top of the piston. The force acting on the top of the
piston is now greater than the force on the bottom and the valve closes.
