All installations and services must be performed by qualified service personnel.
13
Figure 3
FILTER REPLACEMENT
See Table 1 for minimum heating filter areas required for the different types of filters available
should the filter used require replacement.
If the unit is equipped with cooling, contact your installer or a qualified service person to
determine the minimum filter area required for the different filter types and your cooling system.
MINIMUM FILTER AREA REQUIRED
FILTER TYPE
MAX.
RATED
VELOCITY
FILTER AREA FOR HEATING
(LENGTH X WIDTH, SQ. IN.)
-050
-075
-100
-125
THERMO PRIDE *
SUPPLIED
PERMANENT FILTER
600 FT/MIN
176 IN
2
264 IN
2
352 IN
2
440 IN
2
STANDARD
PERMANENT FILTER
500 FT/MIN
211 IN
2
317 IN
2
422 IN
2
528 IN
2
DISPOSABLE TYPE
FILTER
300 FT/MIN
352 IN
2
528 IN
2
704 IN
2
880 IN
2
TABLE 1
* The Thermo Products supplied filter can be cut to size to fit other filter retention systems as
long as the minimum size requirement is met.
NOTICE: Any internal stiffeners used in the filter must not be removed, although they can be
cut to the length required.
