PRINCIPLES OF OPERATION 2
AQUATECH OPERATIONS, SERVICE AND PARTS MANUAL
A Product of Hi-Vac Corporation
PRINCIPLES OF OPERATION
UNIT POWER
The unit power switch supplies power to all the other switches and mounted equipment. When
turning unit off, this switch must be the last one turned off. Push up to turn on the unit power
switch and push down to turn it off. A red light glows inside the switch to indicate that the unit
power is on. Without turning this switch on, nothing will function. The unit power switch should
be turned off when transporting the unit unless using cold weather recirculation.
PTO
In order to keep the truck stationary while operating the water pump, exhauster or both, the rear
axle must be disengaged. This can be done by moving the switch marked PTO to the “Up” or
“On” position. This will cause the PTO to internally shift positions and disengage the rear drive
train of the vehicle. This also engages the hydraulic pumps for system operations of all hydraulic
functions (water pump, boom, tailgate, and tube rack).
ENGAGING THE EXHAUSTER
The same procedure using the switch marked (exhauster) will allow you to engage the vacuum
system. Both power systems can be run simultaneously if desired. When the procedure for
engaging the desired systems is complete, select the gear range referred to on the dashboard
label, or the unit identification section of this manual. Release the clutch.
LOW WATER WARNING AND COLD WEATHER CONDITIONS
The low water control is the center switch on the dashboard. On units equipped with the low
water warning system, a red light will glow in the switch in the event that the water level is
depleted to a pre-determined level. A white light remains on during normal operations. Pushing
the switch up turns on the “winter” low water warning. Pushing the switch down turns on the
“summer” low water warning. The low water switch is labeled “winter” and “summer”. During
cold weather, 32o F (0o C) or below freezing, this switch should be set to the “winter” position.
This will cause the low water warning light to illuminatewith more water left in the water tank.
This allows more water to remain in the tank to help prevent possible freezing. During warm
weather, the switch can be set to the “summer” position, this allows more water to deplete from
the tanks before the low water warning light glows.
HYDRAULICS
The main tower PTO incorporates two additional outputs for the installation of the hydraulic
pump to supply power to all hydraulic functions and the drive system on the water pump. These
pumps are close coupled to the PTO. These drives are automatically engaged whenever the PTO
switch is activated in order to disengage the main drive to the differential of the vehicle. When
the PTO switch is positioned in the “Off” position for drive mode, the hydraulic pump drives are
disengaged.
