39
F
ILTER
R
EMOVAL
Depending on the installation, differing filter arrangements can be applied. Filters can be installed in either the central return
register or a side panel external filter rack (upflow only). A media air filter or electronic air cleaner can be used as an alternate filter.
Follow the filter sizes given in the Recommended Minimum Filter size table to ensure proper unit performance.
To remove filters from an external filter rack in an upright upflow installation, follow the directions provided with external filter rack
kit.
H
ORIZONTAL
U
NIT
F
ILTER
R
EMOVAL
Filters in horizontal installations are located in the central return register or the ductwork near the furnace.
To remove:
1. Turn OFF electrical power to furnace.
2. Remove filter(s) from the central return register or ductwork.
3. Replace filter(s) by reversing the procedure for removal.
4. Turn ON electrical power to furnace.
M
EDIA
A
IR
F
ILTER
OR
E
LECTRONIC
A
IR
C
LEANER
R
EMOVAL
Follow the manufacturer’s directions for service.
B
URNERS
Visually inspect the burner flames periodically during the heating season. Turn on the
furnace at the thermostat and allow several minutes for flames to stabilize, since any
dislodged dust will alter the flames normal appearance. Flames should be stable, quiet,
soft, and blue (dust may cause orange tips but they must not be yellow). They should
extend directly outward from the burners without curling, floating, or lifting off. Flames
must not impinge on the sides of the heat exchanger firing tubes.
I
NDUCED
D
RAFT
AND
C
IRCULATOR
B
LOWERS
The bearings in the induced draft blower and circulator blower motors are permanently
lubricated by the manufacturer. No further lubrication is required. Check motor windings
for accumulation of dust which may cause overheating. Clean as necessary.
C
ONDENSATE
T
RAP
AND
D
RAIN
S
YSTEM
(Q
UALIFIED
S
ERVICER
O
NLY
)
Annually inspect the drain tubes, drain trap, and field-supplied drain line for proper condensate drainage. Check drain system for
hose connection tightness, blockage, and leaks. Clean or repair as necessary.
F
LAME
S
ENSOR
(Q
UALIFIED
S
ERVICER
O
NLY
)
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 sense signal. If the flame sense signal drops too low the furnace will not sense flame and will lock
out. The flame sensor should be carefully cleaned by a qualified servicer using emery cloth or steel wool. Following cleaning, the
flame sense signal should be as indicated in the Specifications Sheet.
F
LUE
P
ASSAGES
(Q
UALIFIED
S
ERVICER
O
NLY
)
The heat exchanger flue passageways should be inspected at the beginning of each heating season.
B
EFORE
L
EAVING
AN
I
NSTALLATION
•
Cycle the furnace with the thermostat at least three times. Verify cooling and fan only operation.
•
Review the Owner’s Manual with the homeowner and discuss proper furnace operation and maintenance.
•
Leave literature packet near furnace.
Burner Flame
Figure 41
