W415-1066 / A / 03.06.12
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4.4 LOCATINg rETurN AIr FILTEr
The hmf100 can be installed with the return air
entering from the left, right, or rear of the furnace.
reTurn Air
reTurn Air
Plenum
Plenum
sTEp #4
• locate and level the hmf100.
• use levelling the legs to compensate for uneven floor and
snug lock nuts up to the furnace base to prevent movement
through vibration.
LEvEL LEg
LOCk NUT
refer to Section 5.0 for clearance to combustibles/Plenum and venting installation.
The hmf100 can be configured to receive the return air plenum of the forced air system on either the left or
right side of the furnace. The furnace is shipped with an air filter and air filter frame, but there are no precut
knockouts in the furnace panels that would receive the air filter frame. instead the side and rear panels are pre
punched with four (4) sets of “l” shape hash marks, which identify the four corners of the rectangular cut out
the installer will be required to make to receive the air filter frame.
in this manner the installer can decide which of the three surfaces is most suitable to receive the return air
plenum.
After cutting rectangular hole in chosen panel insert the air filter frame and bend tabs of inner flanges of air
filter frame back to lock frame in place.
Side PAnel
reAr PAnel