ARMY TM 10-4610-309-14
MARINE CORPS TM 10802A-14/1
0064 00
TACTICAL WATER PURIFICATION SYSTEM (TWPS)
UNIT MAINTENANCE PROCEDURES
COLD WEATHER SYSTEM
WARNING
Electrical hazard. A transformer in good condition produces very high voltage at
the output terminal. The spark plug wire carries high voltage during heater
operation. Before opening up the top cover of the diesel heater to access the
spark plug, be sure the heater power switch is OFF and the power cord is
unplugged from the power source and the heater. Then, when power is required,
be extremely careful not to let any part of your person touch bare wires, leads, or
terminals. Failure to observe this warning may result in injury or death from
electrical shock.
1.
Remove the diesel heater spark plug as follows:
a. Make sure the heater power switch is OFF.
b. Make sure the heater power cord is unplugged from the power source and from the
heater.
c. Open the top cover of the heater by unsnapping the three "screws" at the front of the
cover and lifting the cover.
d. Open the access panel at the top of the heater.
e. Disconnect the spark plug wire.
f. Remove the spark plug using a socket wrench.
2. Test the diesel heater spark plug and transformer as follows (see Figure 14):
a. Check the gap between the spark plug electrodes. The gap should be between 0.045
and 0.055.
b. Adjust the gap between the electrodes if necessary by bending the outside electrode.
c. Reattach the spark plug wire to the spark plug.
d. Establish a good ground between the spark plug and the heater. Be careful not to let any
part of your person become a portion of the grounded circuit.
WARNING
Electrical hazard. After restoring power to the heater to conduct the test, be
extremely careful not to let any part of your person touch the spark plug, bare
wires, leads, or terminals. Failure to observe this warning may result in serious
injury or death from electrical shock.
e. Connect the heater power cord in first at the heater and then at the power source.
f. Set the thermostat switch on the electric control box to the "ON" position.
g. Switch the heater ON. Sparks should appear between the plug's electrodes. If the
ground is good and a spark does NOT jump between the electrodes, replace the spark
plug as described in the next step.
0064 00-20
