PEERLESS PureFire PF-200 Installation, Operation & Maintenance Manual page 20

WATER PIPING AND CONTROLS
Figure 4.1: Piping Symbol Key
4. Y-Type Strainer or Filter Ball
recommends the use of a strainer device in the system to
prevent dirt or sediment from clogging the heat
exchanger. A 20 mesh stainless steel screen is adequate to
protect the heat exchanger. The strainer should be
cleaned often in the first several months of operation. The
Filter Ball ® Valve from Jomar International incorporates a
strainer into a ball valve which allows the technician to
isolate the water circuit while cleaning the strainer.
5. Flow Control Valve: Flow control valves such as the
TACO Flo-Chek or Bell & Gossett Flo-Control™ are
used to prevent gravity circulation by incorporating a
check valve with a weighted disc.
6. Pressure Reducing Valve: A pressure reducing valve,
such as the Bell & Gossett B-38 or a TACO #329, is
used in a hydronic system to automatically feed water
to the system whenever pressure in the system drops
below the pressure setting of the valve. These valves
should not be used on glycol systems unless close
supervision of the glycol solution is practiced.
7. Back Flow Preventer: A back flow preventer (check
valve) is required by some jurisdictions to prevent water
in the hydronic system from backing up into the city
water supply. This is especially important on systems in
which glycol solution is used as the heating medium.
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® Valve: PB Heat 8. Pressure Relief Valve: The boiler pressure relief valve
is shipped separately for field installation.
The valve is to be installed as shown in Figures 4.2 or
WARNING
Do not operate this appliance without installing the
pressure relief valve supplied with the boiler or one
with sufficient relieving capacity in accordance with
the ASME Rating Plate on the boiler heat exchanger.
4.3. Pipe the discharge of the relief valve to within 12"
of the floor and close to a floor drain.
CAUTION
Pipe the discharge of the relief valve as close as
possible to the floor and away from high traffic areas.
Pipe the discharge to a floor drain. Failure to do so
may result in personal injury and/or property
damage.
Provide piping that is the same size or larger than the
relief valve outlet.
9. Low Water Cut Off: When installing a probe type
LWCO, locate the LWCO in the boiler supply above
the top jacket panel. Refer to Section 7. Electrical
Connection in this manual for wiring details.