TM 11-6780-225-35
e. Water Temperature Test.
rected in paragraph 2-8a(2), TM 11-6780-22512.
(1) Operate the water heater at its full capacity for 1
(2) Place a thermometer in one of the drying
hour.
cabinets.
(3) With all operating controls at the full on
(2) The water temperature shall be 150F (65.5C)
position, the thermometer shall indicate a temperature of
+5".
105F (41C) +5 for a period of 1 hour.
f. Water Pressure Test.
d. Relative Humidity Test.
(1) Operate the water system from a water
(1) With the dehumidifier humidistat set to 40
source under pressure (TM 11-6780-225-12).
and all other equipment set to OFF with the darkroom
(2) Observe that the water pump operates
secure, operate the dehumidifier for 2 hours.
from 0 psi to 40 psi as indicated. by the inlet pressure
(2) Measure the relative humidity of the
indicator.
forward compartment of the darkroom with a sling
(3) Turn the adjustment screw of the pressure
psychrometer. The dry bulb and wet bulb temperature
switch (fig. 5-9) with a screwdriver so that the operation
difference shall be 13, indicating a temperature of 60F
O
(15.5C) and a relative humidity of 39 =5 .
of the water pump conforms to step (2) above.
5-2
