Manual

PROBLEM CAUSE SOLUTION

C. Differential pressure relief Differential pressure across Repair shutoff valves

valve does not open No. 1 check valve stays

during test above 2psi due to

leaking outlet gate valve

Weak or broken relief Disassemble and replace

valve spring relief valve spring

Seat tube bound in Disassemble and repair

body O-ring

Plugged hydraulic hose Disassemble and clean

D. Pressure relief valve - Debris on sealing Remove relief valve and

does not close surface clean

Plugged hydraulic Disassemble and clean

hose

Damaged mounting seat gasket Remove relief valve assembly

or seat tube and replace

Ruptured diaphragm Disassemble and replace

diaphragm

Damaged O-ring Disassemble and replace

PROBLEM IDENTIFICATION PROCEDURES - FOR RPZ ASSEMBLIES

SERIES 4000RP AND 5000RPDA

PROBLEM: Continuous or intermittent discharge from relief valve.

1. When using differential pressure gauge 2. Without using differential pressure gauge.

A. Check differential across No. 1 check valve A. Close gate valve No. 2

Reading Problem Result Problem

2 to 3 PSID Leak in No. 1 or No. 2 check valve If discharge stops Leak in No. 2 check valve

4 to 7 PSID and steady Malfunctioning pressure relief valve If discharge does Go to B

not stop

2 to 7 PSID  uctuating Inlet pressure  uctuating

B. Open No. 4 test cock to product a  ow greater

than differential relief valve discharge

Result Problem

If discharge stops Leak in No. 1 check valve

If discharge does Malfunctioning pressure

not stop relief valve