Lennox GCS16-653-75

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16-C7 -- W7400 control system for commercial units without
economizer. Setback is built in. See Figure 86.
FIGURE 86
W7400 THERMOSTAT CONTROL KIT
Control Module
Relay Kit
Heat Pump
Adaptor Relay
J17
P17
NOT USED
J5
P5
J23/P23
17-C7-3 -- W7400 control system for commercial units.
Requires W7400 relay kit and economizer. Warmup
and setback are built in.
18-C8-1 -- W973 control system for commercial units
without economizer or warmup. See figure 87. Re
quires W973 relay kit. Also requires CMC3-1 clock
for night setback.
19-C8-3 -- W973 control system for commercial units with
economizer but without warmup. Requires W973
relay kit. Also requires CMC3-1 clock and night relay
for night setback.
20-C14-1 -- W973 control system for commercial units
with economizer and warmup. Requires W973 relay
kit. Also requires CMC3-1 clock and night relay for
night setback.
FIGURE 87
W973 THERMOSTAT CONTROL KIT
Control Module
Relay Kit
J17
P17
P6
J6
21-C12-1 -- T7300 electronic thermostat for commercial
units without economizer.
22-C12-2 -- T7300 electronic thermostat for commercial
units with economizer. Warmup is built in.
U-Commercial Controls Mounting Box
Commercial Controls Mounting Bracket
The commercial controls box and bracket provide a
mounting location for GCS16 commercial controls. Figure
83 shows the mounting box. The box is designed for use
with GCS16s in downflow return applications. The box uti
lizes the horizontal air opening for this purpose. Figure 88
shows how the box is installed on the GCS16. The bracket
(shown in figure 89) is designed for use with GCS16s in
horizontal return applications. The bracket utilizes the
downflow opening for this purpose.