A 24-volt, 40-ampere generator provides electrical power for the M2 water heater through a voltage
regulator and an electrical power cable.
The control panel (Figure 2) on the front of the pump unit assembly is a one-man station for operating
the M12A1 PDDA. The following paragraphs describe the components of the panel.
Valve 1. This valve (Figure 2) is an offset diaphragm valve. It is used to select the routing of liquids
discharged by the pump. The valve body is in the pump discharge piping.
Valve 2. This valve (Figure 2) is a diaphragm valve. It controls the flow of liquids from the upper
manifold to the lower-hose-reel discharge hose. The valve body is in the lower-hose-reel piping.
Valve 3. This valve (Figure 2) is a diaphragm valve. It controls the flow of liquid from the upper
manifold to the upper-hose-reel discharge hose. The valve body is in the upper-hose-reel discharge
Valve 4. This valve (Figure 2) is a ball valve. It controls the flow of liquid from the prime-detergent
tank through the eductor on the pump. The valve body is in the prime-detergent tank piping.
Pump Drain Valve. The pump drain valve (Figure 2) is a ball valve. It is used to control liquid draining
from the pump. The valve body is in the drain piping. Keep the pump drain valve open when
equipment is not in operation.
Throttle. The push-pull type throttle (Figure 2) controls engine speed. For full throttle, press the throttle
in as far as it will go toward the panel. To decrease engine speed, pull out the knob. Twist the knob for
fine adjustment of engine speed. Use the button lock to lock the throttle at one setting. Pull the throttle
out to its full length of travel to shut off the engine.
Start-Magneto Switch. The start-magneto switch (Figure 2) is a three-position (STOP, RUN, and
START) rotary switch. It controls starter and ignition power to the engine.
Choke. The choke enriches the fuel mixture by restricting the air flow from the carburetor to ease
engine starting. It is located to the right of the start-magneto switch.
Fuel Shut-Off Valve. The fuel shut-off valve (Figure 2) controls the flow of fuel from the fuel tank to
the engine carburetor. The valve body is in the fuel line.