TM 9-4520-258-14
4-7. INSTALLATION INSTRUCTIONS - continued.
b.
Installation Instructions (Refer to Figure 4-4)
(1)
Unwrap power cable (1) and lay aside.
(2)
Loosen four screws (2) and remove supply air duct cover (3) and return air duct cover (4).
NOTE
The ASH unit may be operated either in a closed loop or 100% fresh air configuration. Check
with the operator for intended use prior to connecting the return duct to the heater.
(3)
For recirculating air setup, proceed as follows:
CAUTION
The air ducts may have smooth bends when connected properly. Be careful to avoid sharp
bends, which will restrict air flow. Restrictions will cause equipment damage or improper
operation.
NOTE
Arrows on ducts indicate direction of air flow
(a)
Connect the air supply duct (5) to heater (6) and to the shelter connection. Tighten two clamps
(7) securely.
(b)
Connect the return air duct (8) to heater (6) and to the shelter connection. Tighten two clamps
(7) securely.
(c)
Fresh air can be introduced into the heater unit by adjusting the damper assembly (9). This can
be accomplished at initial setup or by the operator at a later time.
(4) For 100% fresh air setup, proceed as follows:
CAUTION
The air ducts may have smooth bends when connected properly. Be careful to avoid sharp
bends, which will restrict air flow. Restrictions will cause equipment damage or improper
operation.
(a)
Connect the air supply duct (5) to heater (6) and to the shelter connection. Tighten two clamps
(7) securely.
(b)
Do not connect the return air duct (8) to heater (6).
4-8
