Waterous Arizona Operations
500-100 & 120-P Operations
Rev 1
Page 5 of 30
I. Water Pumping Operations
All unit operations begin with pumping water. These steps must be followed for
operations involving pumping water, foam solution, compressed air or compressed
air foam.
1. Connect the hose(s) to the desired discharge(s).
2. If pumping water from an on board booster tank, fully open the tank to pump
valve.
3. If pumping from an overboard source, the tank to pump valve should be fully
closed.
4. Engage the PTO
5. If so equipped, turn on the main power switch to the CAFS unit.
6. Throttle-up to desired pressure.
If pump pressure is absent, it will be necessary to prime the pump.
7. Open desired discharge valve(s) and throttle-up to desired pressure.
CAUTION:
Running the unit with a dry fire pump can cause damage to the pump and
air compressor system.
II. Foam Solution Operations
Follow the instructions above for water pumping operations.
Turn on the foam proportioner to inject foam concentrate into the water stream. Refer
to the foam proportioner operation manual for instructions in the proper operation of
the installed proportioning system.
III. Compressed Air Foam Operations
Follow the instructions above for foam solution operations. Safe operations dictate
the presence of foam concentrate in the water stream prior to the injection of
compressed air. If foam concentrate is not present, a condition known as “slug flow”
will occur. This is where unmixed water and air is discharged through a nozzle in an
erratic manner.
1. Set water discharge pressure at the desired level.
Discharge pressures for compressed air foam operations typically range
between 80 and 120 PSI in a flow state.
NOTE:
Compressed air foam does not have the hydraulic characteristics of plain
water or foam solution. Therefore, standard pump hydraulics practices do not
apply to CAFS operations.
