Specifications

Page 27
FIGURE 31
WIRE TIES
MIXED
AIR
SENSOR
REMD24M
MIXED AIR SENSOR LOCATION
FILTER
e-Wiring, Installation, Maintenance
The economizer uses harness plugs to connect to the
GCS24 unit harness connector located in the filter ac
cess compartment. The 10 and 12.5 ton economizers
are unitary in construction (all one piece). Although har
ness connectors are used to connect the GCS24 to the
economizer, the economizer electrically connects to the
GCS24 differently depending on which control system
has been installed. The different electrical connections
are made in relay kits and controls located in the filter ac
cess area of the unit. All connections (except for enthal
py sensor and mixed air sensor) are made with quick-
connect type harness connectors. For specific details of
economizer wiring and operation, refer to the sequence
of operation section of this manual.
f-Modulating Damper Motor Check
The following procedure checks only the damper motor.
For detailed economizer checkout procedure refer to
Lennox' Solid State Economizer Checkout And Trouble
shooting Guide.
1- Disconnect power. Turn thermostat to OFF position
(occupied mode).
2- Install jumper across contactor K3-2 terminals (see
unit diagram) in unit control box. Install jumper across
enthalpy control terminals T and T1. See figure 32 for
terminal location.
3- Restore power to unit. Outdoor damper should drive
to fully open position (60 to 90 sec. required for full
travel). Observe travel for proper damper operation.
4- Disconnect power to unit. Outdoor damper should
spring return to closed position.
5- Remove T and T1 jumper then restore power to unit.
Outdoor damper should drive to minimum position.
Adjust minimum damper position pot located on con
trol. See figure 32.
FIGURE 32
MODULATING
SOLID STATE ENTHALPY CONTROL
TR TR1
A
BC
D
+
+
5
2
4
T1
P1P
T
1
MINIMUM
POSITIONER
LED
3
6- Disconnect power to unit and remove jumper on
blower relay terminals 6-9. Replace all panels. Re
store power to unit.
D-Transitions
Optional supply/return transition SRT16 is available for use
with GCS24 series units utilizing optional RMF16 roof mount
ing frame. Transition must be installed in the RMF16 mount
ing frame before mounting the GCS24 to frame. Refer to the
manufacturer's instructions included with the transition for de
tailed installation procedures.
E-Supply and Return Diffusers
Optional flush mount diffuser/return FD11 and extended
mount diffuser/return RTD11 are available for use with the
GCS24. Refer to manufacturer's instructions included with
transition for detailed installation procedures.