3
Watts Series 995 Installation Instructions
Installation
A. Series 995 may be installed in a horizontal or vertical flow up posi-
tion (Z995 Series). The shutoff valve with the test cock is to be
mounted on the inlet side of the backflow preventer. The test cock
is on the inlet side of the shutoff valve.
B. The 995 should always be installed in an accessible location to fa-
cilitate testing and servicing. Check the state and local codes to in-
sure that the backflow preventer is installed in compliance, such as
the proper height above the ground. The backflow preventer must be
supported and is not designed to carry full weight of the stand pipe.
C. Water discharge from the relief valve should be vented in accor-
dance with code requirements. The relief valve should never be sol-
idly piped into a drainage ditch, sewer or sump. The discharge should
be funneled through a Watts air gap fitting piped to a floor drain.
D. Watts recommends a strainer be installed ahead of Watts Series
995 assemblies to protect the discs from unnecessary fouling.
*For additional information on Watts insulated enclosures send for ES-WB of ES-WBT
Start Up
E. The downstream shutoff should be closed. Open 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 water hammer or shock damage.
F. The installation of a Watts air gap with the drain line terminating above a
floor drain will handle any normal discharge or nuisance spitting
through the relief valve. However, floor drain size may need to be de-
signed to prevent water damage caused by a catastrophic failure condi-
tion. Do not reduce the size of the drain line from the air gap fitting.
G. Two or more smaller size valves can be piped in parallel (when ap-
proved) to serve a large supply pipe main. This type of installation is
employed where increase capacity is needed beyond that provided by a
single valve and permits testing or servicing of an individual valve with-
out shutting down the complete line.
The number of assemblies used in parallel should be determined by the
engineer’s judgement based on the operating conditions of a specific in-
stallation.
Indoors
Above Ground
*Insulated Enclosure
Watts 995
Vertical
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12" min.
36" max.
Watts N995
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12" min.
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36" max.
Air Gap
To Floor
Drain
Floor Drain
Relief Valve Vent
12" min.
36" max.
Watts Z995
Flow
Summary of Contents for 995 Series
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