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PERSONAL INJURY HAZARD
Caution should be taken to prevent draining where slippery
conditions may cause personal injuries.
Excessive condensate draining may cause saturated soil
conditions which could result in damage to plants.
CONDENSATE DRAIN PROTECTION
Freezing condensate left in condensate trap and drain line may
cause cracks, and possible water damage may occur. If freeze
protection is required, use condensate freeze protection accessory
or equivalent 3 to 6 watt per ft at 120-v and 40°F self-regulating,
shielded, and waterproof heat tape. See Installation Instructions
supplied with accessory or heat tape manufacturer’s recommenda-
tions.
1. Fold heat tape in half and wrap on itself 3 times.
2. Locate heat tape between sides of condensate trap back. (See
Fig. 47.)
3. Use wire ties to secure heat tape in place. Wire ties can be
positioned in notches of condensate trap sides. (See Fig. 47.)
4. Wrap field drain pipe with remaining heat tape, approximately
1 wrap per ft.
5. When using field-supplied heat tape, follow heat tape manu-
facturer’s instructions for all other installation guidelines.
START-UP ADJUSTMENT AND SAFETY CHECK
FURNACE MAY NOT OPERATE
Failure to follow this caution may result in furnace operation
stopping and water pipes freezing during cold weather.
Furnace control must be grounded for proper operation, or
control
will
lock
out.
Control
is
grounded
through
green/yellow wire connected to gas valve C-terminal and
burner box screw.
Step 1—General
The furnace must have a 115-v power supply properly connected
and grounded.
NOTE:
Proper polarity and proper grounding must be maintained
for 115-v wiring. If polarity is incorrect, control status indicator
light will flash rapidly and the furnace will not operate.
Natural gas service pressure must not exceed 0.5 psig (14-in. wc),
and be no less than 0.16 psig (4.5-in. wc).
Thermostat wire connections at R and W/W1 are the minimum
required for gas heating operation. W2 must be connected for
2-stage heating thermostats. C
OM
, Y/Y2, and G are required for
cooling, heat pumps, and some clock thermostats. These must be
made at the 24-v terminal block on the control. (See Fig. 37.)
This furnace can be installed with either a single-stage heating or
a 2-stage heating thermostat.
For single-stage thermostats, connect thermostat W to W/W1 at
furnace control terminal block. (See Fig. 31 and 50H.) For
single-stage thermostats, the control will determine, based on
length of previous heating on and off cycles, when to operate in
low- and high- gas heat for optimum comfort. Setup switch-1
(SW-1) must be in the factory-shipped OFF position. See Fig. 36
and Table 11A and B for setup switch information.
If a 2-stage heating thermostat is to be used, move SW-1 to ON
position at end of furnace installation. This overrides built-in
control process for selecting high and low fire and allows the
2-stage thermostat to select gas heating modes. The W2 from
thermostat must be connected to W2 on control terminal block.
(See Fig. 32 and 50A-G.)
Before operating furnace, check each flame rollout manual reset
switch for continuity. If necessary, press and release button to reset
switch. The blower compartment door must be in place to
complete the 115-v circuit to the furnace.
Fig. 46—Example of Field Drain Attachment
A94054
OPEN STAND
PIPE FOR
A/C OR
HUMIDIFIER
DRAIN
TEE
TO OPEN
DRAIN
Fig. 47—Condensate Trap Heat Tape
A93036
CONDENSATE TRAP
WIRE TIE(S)
HEAT TAPE
(3 WRAPS MINIMUM)
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