Wilkins Reduced Pressure Principle 375XL 1-1/4”

Close inlet and outlet shut-off valves

Open test cocks to release pressure from valve

Unscrew screws holding body down and lift valve body upward

Twist and remove sleeve from body and push checks out of body inlet

Remove spring retainers to access poppets

Inspect the rubber seal ring for cuts or embedded debris

Invert the seal ring if reverse side is unused

Inspect seat surface for nicks or dings and replace if necessary

Ensure Differential pressure gauge test kit is available

Attach the "HIGH" hose to test cock #2 and the "LOW" hose to test cock #3

Test No. 1 - #2 Check Valve Tightness

Open by-pass valves "C" and "A" and bleed to atmosphere until all air is expelled

Close by-pass valve "A". Open by-pass valve "B" and bleed to atmosphere until all air is expelled. Close by-pass valves "B" and "C"

Attach the "VENT" hose to test cock #4

Remove three bolts holding relief valve module to body

Pull down and remove relief module to expose seat and seal ring

Inspect parts without further disassembly

Ensure small o-ring and large o-ring are not lost

Remove the four screws holding the two module halves together

Ensure small o-ring is not lost