Watts 995 Series, Installation, Service, Repair Kits, Maintenance

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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