© 2006
GE ECM
by Regal-Beloit
- 47 -
Indoor Blower Motors
v0.2
Some furnace manufactures and many air handler manufactures include the filter in
the ESP rating. If this is the case the ESP reading in the return would be taken
before the filter. However, if the filter used is not the style or size that the
manufacturer specified it may be more restrictive than they rated for.
Air handlers and package systems that have the evaporator coil inside their cabinet
include them in the ESP rating. If this is the case the ESP reading would be taken at
the return and supply connections depending on where the filter is and if it is also
included in the rating.
Filters are also a common airflow restriction problem. Most filters supplied and
recommended by the manufacturer are not very restrictive. That is to say that they
are good at moving air but bad at catching the dust and dirt that we want to keep out
of the system and remove from our air. Many times these filters get replaced with
higher efficiency filters that are good at catching dust and dirt but will be bad at
moving air if they are not sized properly.
Evaporator
“Slant Coil”
F
il
te
r
Return
Supply
0-
.5-
1-
- .15 in. wc.
+ .35 in. wc