All installations and services must be performed by qualified service personnel.
D. Return Air Filter
The Return Air Filter(s): Provided with this unit is a permanent type filter. This filter(s) should be inspected and when dirty, cleaned or replaced, if necessary to assure proper furnace operation. Follow the cleaning, removal and replacement procedure below.
Filter Maintenance Procedure:
The filter rack will be located between the return air plenum and the return air opening of the furnace. See Figure 11 for MHA1/MDA1 series units. Slide dirty filter out of the filter rack. Clean the filter by vacuuming, rinsing with tap water, hosing or dipping in an ordinary detergent solution. After cleaning, replace the completely dry filter in the rack. If the filter has a mesh, the mesh side of the filter must be towards the furnace.
FILTERS
RETURN AIR
SUPPLY AIR
| RETURN |
| AIR |
FRONT DOOR | BLOWER |
| ACCESS |
| DOOR |
COMBUSTIBLE
FLOOR BASE
TYPICAL FILTER
LOCATION
MHA1 SERIES
SUPPLY AIR
MDA1 SERIES
Figure 11: Filter Location
FILTER REPLACEMENT
Should the filter used require replacement, see Table 2 in Section II, I, of this manual for minimum filter areas required for the different types of filters available to ensure an adequate replacement is selected.
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