Switch

TM 5-6640-213-14

(3) Switch. The switch is held in place by means of

spring clips. To replace it, tag the lead wires with respect to

their relative positions and detach them from the switch, compress the

clips, and push the switch outward from the back of panel. Press in

the new switch and attach the proper wires to it.

Do not crimp or sharply bend the thermostat bulb

capillaries.

(4) Thermostat. When the safety thermostat takes over

control of the chamber temperature the control thermostat is faulty.

When thermostat failure occurs, it is simpler and quicker to install

the entire assembly because a certain amount of calibration and adjust-

ment is necessary if only part of the unit is replaced. Replace the

entire thermostat assembly as follows:

(a) Disengage the thermostat bulbs from the retaining

clamps by twisting the clips at the bottom of the chamber.

(b) Carefully remove the bottom diffuser panel and

remove the control panel.

assembly. Remove the control knob setscrews and the screws holding

the assembly to the control panel.

(d) Work the thermostat bulbs out of the chamber.

(e) Reverse the above procedure to install the new

thermostat assembly.

(5) Heater.

Replace a defective heater as follows:

(a) Disengage both thermostat bulbs from the retain-

ing clips on the bottom diffuser panel in the chamber.

(b) Remove the bottom diffuser panel by removing the

retaining screws. Work the thermostat bulbs upright and lift the

panel out of the chamber, carefully sliding the bulbs through it

while noting the hole through which the bulbs were placed.

allow the bus bars to slip down through the porcelain insulators or

the control panel will have to be removed to push the bars back.

(d) Lift the heater fro# the chamber, install the new

heater, and reconnect the bus bars.

(e) Work the two thermostat bulbs through the hole

previously marked in the bottom diffuser panel.

(f) Replace the panel and secure it.

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