TM 5-3825-229-14&P
2-2. WATER DISTRIBUTOR VALVES
The water distributor valves consist of three large, manually operated valves, a pair of solenoid actuated air
control valves, and two pair of small manually operated air control valves. As a group, these valves control the
flow of water for all operations of the water distributor system. Refer to valve operation plate (para. 2-11).
aSuction Valve. The suction valve is located in
the line between the tank and the pump intake. The valve
is closed when the valve handle is pointing down, and
open when the valve handle is pointing toward the front of
the semitrailer. The words OPEN and SHUT are stamped
on the indicator plate. The stampings may be wrong. You
must squeeze the handle to adjust the position of the valve
plate.
b.
Fill Valve. The fill valve is located in the return
line between the pump and the tank. The valve is closed
when the valve handle is pointing down, and open when
the valve handle is pointing toward the front of the
semitrailer. The words OPEN and SHUT are stamped on
the indicator plate. You must squeeze the handle to adjust
the position of the valve plate.
c.
Discharge Valve. The discharge valve is located
directly above the fill valve. Open the valve by turning the
handle fully counterclockwise. Close the valve by turning
the handle fully clockwise. The discharge port of the valve
is threaded to accept the 1-1/2" fire hose supplied with the
semitrailer. A threaded cap is provided for
use when the fire hose is not connected. This cap should be kept on whenever the valve is not in use.
WARNING
The discharge valve must always be closed before removing the cap or discharge hose, and whenever there is
nothing connected to the output of the valve. This will prevent possible serious injury to personnel and damage to the
equipment.
d.
Spray Nozzle Control Valves. These valves are held in their normally closed position by an internal spring. When
the water distributor is coupled to a towing vehicle, air pressure taken from the brake system adds support to the spring in
holding the spray nozzle control valves closed even when the water pump has pressurized the system. When a spray
nozzle switch on either control panel is moved to the ON position, air pressure to the spray nozzle control valve is
interrupted, allowing the system water pressure to overcome the spring inside the spray control nozzle valve which then
opens to water flow.
e.
Manually Operated Air Pressure Control Valves. There are two manually operated air pressure control valves for
each spray nozzle valve. These valves are open when the handle of the valve is in line with the valve fittings, and closed
when the handle is turned one-quarter turn (900). When the semitrailer is connected to a truck-tractor, all valves should
be configured for normal operation as shown. For emergency firefighting, or for any other situation where it is necessary
to pump water without a truck-tractor connected to the water distributor, each of the four valves must be turned one-
quarter turn (900) as shown. This causes equal water pressure on both sides of the valve, allowing the spring to hold the
spray nozzle valve closed in place of the air pressure that normally holds it closed.
2-3