Graco 25T818, Instructions, Repair And Parts

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Installation
3A8571A 9
Installation
Grounding
NOTE: The reference numbers in the following
instructions refer to Parts , page 28.
System Plumbing
The On-Demand pump delivers a constant output flow,
even with a varying load.
It is important that the system plumbing be of adequate
size so that the back pressure does not exceed 200 psi
(1.38 MPa, 13.8 bar).
All plumbing and hoses used in the installation should
have a minimum pressure rating of 325 psi (2.24 MPa,
22.4 bar).
If the system pressure drop at the rated pump flow is
greater than, or close to, the pressure switch setting,
the motor will cycle on and off when the dispense valve
is opened to dispense fluid. If this happens, reduce
system pressure by using a larger diameter hose or by
using a less restrictive valve.
Graco recommends using 1/2 in. ID hose to keep the
working pressure low while the dispense valve is being
triggered. The output line fluid pressure should not
exceed 200 psi (1.3 8 MPa, 13.8 bar) while pumping
fluid.
The pump design includes a self-contained pressure
relief valve (C), Component Identification , page 7.
When activated, the valve relieves pressure back to the
tank.
Mount Pump on Tank with
Suction Tube
1. Install the bung adapter (15) in the tank bung and
tighten.
2. Use a 3/4 in. (19 mm) steel or PVC pipe with a
3/4 npt pipe threads on one end as a suction tube.
3. Measure the length from the top of the bung
adapter to the bottom of the tank. Cut the suction
tube length to 1/2 in. (13 mm) less than this
measurement.
4. Apply pipe thread sealant to suction tube threads
and install the pipe into the pump inlet.
5. Insert suction tube assembly through the bung
adapter and lower the pump onto the bung
adapter.
6. Position the pump so that the outlet port is in the
desired position. Tighten the swivel nut (20) on the
pump to the bung adapter.
The equipment must be grounded to reduce the risk
of static sparking. Static sparking can cause fumes
to ignite or explode. Grounding provides an escape
wire for the electric current.
NOTICE
Never allow the pump to operate dry. Make sure that
the pump has fluid in it when the pump is initially
installed. Do not run the pump for more than five (5)
minutes with the pump discharge blocked. Do not
operate the pump continuously more than 30 minutes
in one (1) hour. Failure to follow these instructions can
result in damage to the pump.