TM 5-4520-256-14
2-6. ASSEMBLY AND PREPARATION FOR USE - Continued.
h. Recirculating Air Setup. To set up the unit as a recirculating air unit, perform steps a. through g. above.
i. 100% Fresh Air Set-Up. To operate as a fresh air unit using 100% fresh air, proceed as follows:
(1) Perform steps a. through g. above but do not connect the return air duct. Be sure to remove the return air duct
cover.
(2) Open the fresh air damper above the control panel by lifting pendant and chain upward and allow chain to feed
into cabinet.
2-7. OPERATING PROCEDURES. These procedures consist of the following:
a. Ventilation Mode Operation. (Refer to Figure 2-8).
CAUTION
* Do not operate unit without fuel. Operation without fuel will result in damage to the fuel pump.
* Be sure INTERNAL TANK/EXTERNAL TANK switch is in the proper position to supply fuel to
fuel pump.
(1) Perform the setup procedures in paragraph 2-6.
(2) Press the circuit breaker CB1 (2) button.
(3) Set the OFF/VENT/HEAT selector switch S1l (1) to VENT. The centrifugal fan should begin operating
immediately.
(4) Adjust the fresh air damper (3) above the control panel, for the desired amount of fresh air.
2-18
