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UNIT CORROSION HAZARD
Excessive exposure to contaminated combustion air may
result in safety and performance related problems.
Combustion air must not be taken from inside structure
because inside air is frequently contaminated by halogens,
which include fluorides, chlorides, bromides, and iodides.
These elements are found in aerosols, detergents, bleaches,
cleaning solvents, salts, air fresheners, adhesives, paint, and
other household products. Locate combustion-air inlet as far
as possible from swimming pool and swimming pool pump
house.
NOTE:
All pipe joints must have cemented attachment of
combustion-air inlet pipe to inlet housing connection, since it may
be necessary to remove pipe for servicing.
Assembly of Combustion Air Pipe (Non-Direct Vent/1-Pipe
System ONLY)
1. Permanently install perforated disk assembly (factory-
supplied in loose parts bag) in combustion-air elbow using
RTV or by cementing, as shown in Fig. 39. For 120,000 Btuh
size units only: separate the 2 halves of perforated disk
assembly and use only the shouldered disk half.
2. Determine the length of straight portion of combustion-air
inlet pipe from Fig. 39.
3. Cut field-supplied 2-in. diameter PVC pipe to length as
determined per Fig. 39.
4. Permanently attach elbow/perforated disk assembly to straight
portion of pipe using RTV or by cementing as shown in Fig.
39.
Assembly of Combustion Air Pipe (Direct Vent-2-Pipe
System ONLY)
1. Using Table 12, determine the smallest combustion air diam-
eter permitted. Pick the larger diameter and use it for both
combustion and vent pipe.
NOTE:
Do not count elbows or pipe sections in terminations or
within furnace (All elblows shown in Fig. 44 and Fig. 45 are not
to be counted).
UNIT MAY NOT OPERATE
Failure to follow this caution may result in incomplete
combusiton, flame disturbance, or flame sense lockout.
When installing combusiton air and vent system of short pipe
length, the smallest allowable pipe diameter must be used.
NOTE:
A 2-in. diameter pipe must be used within furnace casing.
Make all pipe diameter transitions outside furnacec casing per Fig.
41.
2. If required per Table 12, insert perforated disk assembly
(factory-supplied in loose parts bag) in intake housing where
combustion air pipe will be connected. If half disk set is
required, install only shouldered disk half.
Fig. 37—Control Center
A02017
LHT
OFF
DLY
ON
OFF
W2
BLW
24-V-THERMOSTAT
TERMINALS
SETUP SWITCHES
LOW-HEAT ONLY AND
BLOWER OFF-DELAY
TWINNING AND/OR
COMPONENT TEST
TERMINAL
ACRDJ - AIR CONDITIONING
RELAY DISABLE JUMPER
TRANSFORMER 24-VAC
CONNECTIONS
PL1 - LOW VOLTAGE MAIN
HARNESS CONNECTOR
PL3 -ICM CONTROL
HARNESS CONNECTOR
HUMIDIFIER TERMINAL
(24-VAC 0.5 AMP MAX.)
3-AMP FUSE
LED OPERATION &
DIAGNOSTIC LIGHT
115-VAC (L2) NEUTRAL
CONNECTIONS
PL2 - HOT SURFACE
IGNITER & INDUCER
MOTOR CONNECTOR
115-VAC (L1) LINE
VOLTAGE CONNECTION
EAC-1 TERMINAL
(115-VAC 1.0 AMP MAX.)
BLOWER SPEED
SELECTION TERMINALS
HI HEAT
LO HEAT
SPARE-1
SPARE-2
COOL
Y1
DHUM
G
COM
24V
WW1
Y/Y2
R
TEST/TWIN
HUM
1 2 3
PL
T
A
CRDJ
0.5-AMP024 VAC
FUSE 3-AMP
SEC-1
SEC-2
PL1
NEUTRAL-L2
1
EAC-2
BHT/CLR
BHI/LOR
PL3 1
BLWR
COOL
SPARE-1
SPARE-2
1-AMP@115 VAC
EAC-1
PR-1
IDR
HSIR
IDM
IHI/LOR
PL2
1
HSI HI LO
STATU
S
C
OD
EL
E
D
HI HEA
T
LO HEA
T
L1
31