Table 2A — Minimum Airflow for
Electric Heater Operation; 60 Hz
UNIT
TYPE
MINIMUM AIRFLOW (Cfm)
Unit Size
018
024
030
036
042
048
060
HEAT PUMP
700*
800
1000
1300
1300
1600
1750
ELECTRIC
COOLING
700*
700
875
1200
1225
1400
1750
*Not applicable to High Efficiency units.
Table 2B — Minimum Airflow for
Electric Heater Operation; 50 Hz
UNIT
TYPE
MINIMUM AIRFLOW (L/s)
Unit Size
024
030
036
048
060
HEAT PUMP
338
472
614
755
826
ELECTRIC
COOLING
330
413
567
661
826
Heater Installation (Vertical Airflow
Configuration)
1. The unit must first be converted to vertical airflow con-
figuration before the electric heater package is installed.
Refer to unit Installation Instructions.
NOTE: If heat pump units have already been factory con-
verted to vertical airflow configuration, skip to Step 6.
2. Remove blower/control box access panel. See Fig. 2.
3. Disconnect indoor-fan motor leads from indoor-fan re-
lay and unit contactor. Disengage wire tie securing wires
to the unit control box. See Fig. 12.
4. Remove indoor blower assembly. Remove screws
securing the filler bracket and relocate filler bracket to
vertical airflow application as shown in Fig. 13.
5. Remove the blower assembly support bracket. The screws
securing the support bracket can be accessed by remov-
ing the condenser side grille. Discard support bracket
and retain screws. Using the 2 speed nut clips provided
with the kit, reinsert the screws through the partition and
tighten to ensure watertightness. See Fig. 13.
6. Remove the electric heater and control box assembly from
packaging and remove safety shield from heater tray.
See Fig. 14.
7. Remove the plug holding the heater wiring bundle to
the heater tray, being careful not to damage wiring. Loosen
nuts on the heater terminals that hold the heater power
leads and ring terminals in place. See Fig. 15. Rotate the
wiring 180 degrees, so that the heater power leads now
leave in the opposite direction from the heater tray. Tighten
the nuts holding the heater power leads and ring ter-
minals. Secure wire tie by inserting it into the engage-
ment hole in heater tray.
8. Mount the safety shield over the limit switches using
2 screws provided. See Fig. 16.
9. Mount the electric heater assembly onto the indoor blower
housing. Insert the tabs on the heater assembly into the
slots closest to the blower wheel inlet. Secure to hous-
ing with 2 screws provided in kit. See Fig. 17.
10. Orient blower housing for vertical airflow and slide into
vertical opening, making sure the flanges on the blower
side plates engage the tabs in the unit basepan. When
the blower housing is near final position, resistance will
be felt as the blower housing contacts the basepan in-
sulation. This resistance can be overcome by applying a
slight force to the base of the blower. Continue sliding
blower until hole in side plate flange aligns with the hole
in the basepan. Secure blower to unit using screws re-
moved in Step 5.
11. Install electric heater control box by engaging the tabs
back of the heater control box with the slots in the back
of the unit control box. Secure the heater control box
using the screws provided.
SECURE
HIGH-
VOLTAGE
BUNDLE
HERE
LOW-
VOLTAGE
CONNECTION
SPLICE BOX
Fig. 7 — Accessory Electric Heater
Low-Voltage Wiring
Fig. 8 — Low-Voltage Wiring, Single-Stage
Electric Heaters
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