(c)
Move the clamp-on ammeter to the ground wire.
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(d) Make sure that the current in the ground wire is the same as that found in the power wire.
S 085-036
(5)
Remove the clamp-on ammeter.
S 415-048
(6)
Install the cargo liners or floor panels (AMM 25-52-01/401).
S 715-046
(7)
Do the same test procedure for a mid or water tank in-line heater.__________
___
S 865-049
(8) Close 414A24, WASTE & WATER LINE HTR MN PWR (gnd) circuit breaker on the P414, Left Power Distribution Center.
M. Potable Water Tank Heater Test
S 015-064
(1)
Remove the applicable cargo liners or floor panels to get access to the tank heater (AMM 25-52-01/401).
S 485-060
(2)
Connect a clamp-on ammeter around one of the heater power wires.
S 715-061
(3)
Do a check of the tank heater operation:
(a) Make the heater thermostat cool with dry ice or coolant spray (the thermostat is in the tank next to the heater).
NOTE: To use the coolant spray, apply the spray to the
____ thermostat for 2 seconds. After 5 seconds apply the spray again. Do this procedure as many times as necessary to make the thermostat sufficiently cool.
(b) Make sure the current is 0.7 amps or more.
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S 085-065
(4)
Remove the clamp-on ammeter.
S 415-063
(5)
Install the cargo liners or floor panels (AMM 25-52-01/401).
N. Test of the Heated Supply Hose Below the Water Tank
S 865-077
(1) Make sure these circuit breakers are closed:
(a) P414 Panel:
1) 414A23, WATER TANK HEATERS-B
2) 414D4, WATER TANK HEATERS-A
S 015-071
(2)
Remove the applicable cargo liners to get access to the water tank (AMM 25-52-01/401).
S 485-072
(3)
Connect a clamp-on ammeter around one of the heater power wires.
S 725-074
(4)
Do a check of the heated hose operation:
(a) Make the heater thermostat cool with dry ice or coolant spray (the thermostat is part of the heated hose assembly).
NOTE: To use the coolant spray, apply the spray to the
____ thermostat for 2 seconds. After 5 seconds apply the spray again. Do this procedure as many times as necessary to make the thermostat sufficiently cool.
(b) Make sure the current is 0.5 amps or more.
S 085-075
(5)
Remove the clamp-on ammeter.
(6)
Install the cargo liners that were removed (AMM 25-52-01/401).
S 415-076
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RIBBON HEATERS - REMOVAL/INSTALLATION
_____________________________________
1. General_______
A. This subject has two tasks, one for the removal and one for the installation of the water line and waste drain ribbon heaters. In this procedure, you will get access to the heater, cut the electrical leads, remove tape from the heater, install the replacement heater, and make splices at the new heater wires.
B. The procedure for individual water line ribbon heaters are the same except for the number of inches between the turns on the hoses.
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