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Pumping from Hydrant or Relay
Follow the instructions to operate the pump from hydrant or relay.
High Pressure Hazard:
Prior to connection of hoses, caps or other
closures with pump intake or pump discharge connections, relieve
pressure by opening drains.
Scalding Water Hazard:
When operating the pump, be sure to open at
least one discharge valve slightly to prevent the pump from overheating.
If the pump runs for a few minutes completely closed, it may heat the
water enough to scald someone when the valve is opened. Overheating
can damage the packing, seals and other pump parts. If the apparatus
builder has installed a by-pass system or other provision designed to
prevent overheating, opening a discharge valve may be unnecessary.
Unexpected Truck Movement:
Failure to properly shift transmission in
accordance with the transmission operating instructions may result in
unexpected truck movement which may result in serious personal injury
or death.
1. Engage the pump—refer to the pump transmission instructions for your
application.
2. Open intake, hydrant and other valves as necessary to allow water to enter
the pump.
NOTE:
Bleeder valves should be used while filling a hose connected to an
intake with water.
3. Switch transfer valve to desired position.
NOTE:
As a general rule, keep the transfer valve in pressure position when
pumping up to 2/3 of the rated capacity of the pump and in volume
when pumping more than 2/3 of the rated capacity. If high pressure
is required (more than 200 psi, 13.8 bar), operating the pump in the
pressure position may be necessary even if it means closing one or
more valves to reduce volume and avoid cavitation. The transfer valve
may be changed from one position to the other while operating the
pump. Decreasing the discharge pressure will make this easier. If the
pump has a manually operated transfer valve, slow engine speed to
reduce the discharge pressure to 75 psi (5.2 bar) or less. With the
electric transfer valve, reducing the discharge pressure is necessary
only if it exceeds 250 psi (17.3 bar).
4. Open discharge valves and accelerate engine to obtain desired discharge
pressure and capacity.
5. Set relief valves or other pressure governing device to desired pressure.
NOTE:
Do not attempt to pump more water than is available from the
hydrant. Always make sure the intake pressure compound gauge
reading stays above zero. Some fire departments operate at a
minimum intake pressure of 10 psi (0.7 bar) when pumping from
hydrant to prevent a “soft” intake hose from collapsing.
After operation do the following:
High Pressure Hazard:
Prior to removal of hoses, caps or other
closures with pump intake or pump discharge connections, relieve
pressure by opening the drains.
1. Disengage the pump—refer to the pump transmission instructions for your
application.
2.
If pumping other than clean water during operation, flush the pump until all
contaminants are removed.
3. Close all drains and install intake and discharge caps.
4. Switch transfer valve back and forth once.
