35
MAINTENANCE
Model
Minimum Recommended Filter Size^
*MEC960303AN*
1 - 16 X 25 Side or 1 - 14 X 25 Bottom
*MEC960403AN*
1 - 16 X 25 Side or 1 - 14 X 25 Bottom
*MEC960603AN*
1 - 16 X 25 Side or 1 - 14 X 25 Bottom
*MEC960302BN*
1 - 16 X 25 Side or Bottom
*MEC960402BN*
1 - 16 X 25 Side or Bottom
*MEC960603BN*
1 - 16 X 25 Side or Bottom
*MEC960803BN*
1 - 16 X 25 Side or Bottom
*MEC960804CN*
1 - 16 X 25 Side or Bottom
*MEC961004CN*
1 - 16 X 25 Side or Bottom
*MEC961005CN*
1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*MEC961205DN*
1 - 20 X 25 Bottom / 2 - 16 X 25 Side Return
*CEC960403BN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CEC960603BN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CEC960803BN*
2 - 10 X 20 or 1 - 16 X 25 Top Return
*CEC961005BN*
2 - 14 X 20 or 1 - 20 X 25 Top Return
Filter Sizing Chart
^ Larger filters may be used, filters may also be centrally located
FLAME SENSOR (QUALIFIED SERVICER ONLY)
Under some conditions, the fuel or air supply can create a
nearly invisible coating on the flame sensor. This coating
acts as an insulator, causing a drop in the flame sensing sig
-
nal. If this occurs, a qualified servicer must carefully clean
the flame sensor with steel wool. After cleaning, the flame
sensor output should be as listed on the specification sheet.
BURNERS
WARNING
HIGH
VOLTAGE
E
LECTRICAL COMPONENTS ARE CONTAINED IN BOTH
COMPARTMENTS.
T
O AVOID ELECTRICAL SHOCK, INJURY OR
DEATH, DO NOT REMOVE ANY INTERNAL COMPARTMENT COVERS
OR ATTEMPT ANY ADJUSTMENT.
C
ONTACT A QUALIFIED
SERVICE AGENT AT ONCE IF AN ABNORMAL FLAME
APPEARANCE SHOULD DEVELOP.
Periodically during the heating season make a visual
check of the burner flames. Turn the furnace on at the
thermostat. Wait a few minutes since any dislodged dust
will alter the normal flame appearance. Flames should be
stable, quiet, soft and blue with slightly orange tips. They
should not be yellow. They should extend directly outward
from the burner ports without curling downward, floating or
lifting off the ports.
Check the
Burner Flames for:
1. Stable, soft and blue.
2. Not curling, floating
or lifting off.
Burner Flame
TEST EQUIPMENT
Proper test equipment for accurate diagnosis is as essential
as regular hand tools.
The following is a must for every service technician and
service shop.
1. Dial type thermometers or thermocouple meter (op
-
tional) - to measure dry bulb temperature.
2. Amprobe - to measure amperage and voltage.
3. Volt-Ohm Meter - testing continuity, capacitors, and
motor windings.
4. Inclined Manometer - to measure static pressure,
pressure drop across coils, filters, and draft.
5. Water Manometer (12") - to test gas inlet and mani
-
fold pressure.
Other recording type instruments can be essential in solving
abnormal problems, however, in many instances they may
be rented from local sources.
Proper equipment promotes faster, more efficient service
and accurate repairs resulting in fewer call backs.
