Graco 234192, Instructions Manual

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Installation
Fluid Pressure Relief Valve
CAUTION
Some systems may require installation of a pres-
sure relief valve at the pump outlet to prevent
overpressurization and rupture of the pump or
hose. See Fig. 2.
Thermal expansion of fluid in the outlet line can
cause overpressurization. This can occur when
using long fluid lines exposed to sunlight or ambi-
ent heat, or when pumping from a cool to a warm
area (for example, from an underground tank).
Overpressurization can also occur if the herkules
pump is being used to feed fluid to a piston pump,
and the intake valve of the piston pump does not
close, causing fluid to back up in the outlet line.
Connect fluid outlet line here.
Fig. 2
KEY
A 3/8 npt(f) fluid inlet port
B 3/8 npt(f) fluid outlet port
C Pressure relief valve
Part No. 112119 (stainless steel)
1
3
2 Connect fluid inlet line here. Use a compat-
ible liquid thread sealant or PTFE tape on
connection to prevent air from getting into
the material line.
Install valve between fluid inlet and outlet ports.
C
A
B
1
2
3
01539B
1