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9

Problem

Cause

Solution

A. Assembly discharges from

Fouled first check

Disassemble and clean No. 1

differential relief valve during

check valve

no flow condition.

Fluctuating inlet pressure

Control supply line water pressure.
Install a spring-loaded soft seated
check valve upstream of the back-
flow prevention assembly.

Outlet pressure higher than inlet

Disassemble, clean #2 check valve

pressure & leak in No. 2 check valve

& identify cause of back pressure

Leak through diaphragm

Service relief valve

Pressure relief valve does not close

See problem D

B. Assembly discharges from

Pressure relief valve does not close

See problem D

differential relief valve during a
flow condition.

C. Differential pressure relief valve

Differential pressure across No. 1

Repair shutoff valves

does not open during test

check valve stays above 2.0 psi
due to leaking outlet gate valve

Weak or broken relief valve spring

Disassemble and replace relief
valve spring

Plugged hydraulic hose

Disassemble and repair

D. Pressure relief valve

Debris on sealing surface

Remove relief valve and clean

does not close

Plugged hydraulic hose

Disassemble and clean

Damaged seat or rubber shutoff disc

Remove relief valve assembly and
replace

Ruptured diaphragm

Disassemble and replace diaphragm

Trouble Shooting Guide

Содержание 995 Series

Страница 1: ...IS TK 99E and IS TK 99D For troubleshooting guide send for S TSG For other repair kits and service parts send for PL RP BPD For technical assistance contact your local Watts representative on back pag...

Страница 2: ...nd cause water blockage during an emergency 5 Normal discharge and nuisance spitting are accommodated by the use of a Watts air gap fitting and a fabricated indirect waste line Floor drains of the sam...

Страница 3: ...pen upstream slowly fill the valve and bleed the air through Test cock 2 3 and 4 When valve is filled open the downstream shutoff slowly and fill the water supply sys tem This is necessary to avoid wa...

Страница 4: ...o secure cam bar Slowly pull the assembly out ward to open check allowing exposure of the seat and clapper contact area for cleaning The assembly may be locked open by aligning the holes in the cam ba...

Страница 5: ...removable 1 3 Clapper Retaining Plate Screws removable 4 4 Clapper Retainer Plate removable 1 5 Clapper Disc removable 1 6 Pivot Arm Pin removable 2 c clips 1 7 2nd Cam Check O ring removable 1 Parts...

Страница 6: ...t the elastomer in the sealing disc assembly 4 Servicing the Relief Valve COMPLETE DISASSEMBLY OF THE RELIEF VALVE 1 Remove the sealing disc as above 2 Remove the dust cover 10 from the cover weldment...

Страница 7: ...ush Start Test 7 Open VA then slowly open VB no more than 1 4 turn When relief valve drips push the hold button for 2 seconds Record reading must be 2 PSID or more Push Stop Test 8 Close VA and VB Tes...

Страница 8: ...Kits include RV Diaphragm RV Disc Lower O ring Upper O ring First Check Rubber Parts Kit 888923 RK 995 995 RPDA RC1 3 4 3 4 995 995 RPDA 888924 RK 995 995 RPDA RC1 6 6 995 995 RPDA Kits include First...

Страница 9: ...blem D B Assembly discharges from Pressure relief valve does not close See problem D differential relief valve during a flow condition C Differential pressure relief valve Differential pressure across...

Страница 10: ...nd for F TK DL No TK 7 Backflow Preventer Test Kit Tests the individual check modules of the Watts No 7 Residential Dual Check Also used to test No 709 and 007 For additional information send for IS T...

Страница 11: ...11 NOTES...

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