33
ComPac 9/04-12
Important: Be sure that the crankcase heater (if used) has been energized for at least
24 hours before starting the unit(s). Double-check all electrical connections before
applying power.
Procedure:
1. Set the cooling temperature on the wall thermostat to a point higher than the ambient
temperature. Set the heating temperature to a temperature that is lower than the
ambient.
2. Set the thermostat system switch in the AUTO position. Nothing should operate
at this time.
3. Set the time delay in the ComPac
®
I or ComPac
®
II A/C control box to three minutes.
Check the changeover setting of the H205A or dry bulb sensor and reset it if needed
(ComPac II A/C only). See Section 1.6.
4. Slowly lower the thermostat's cooling temperature until the switch closes. The indoor
fan should operate.
Once the indoor fan turns on, allow approximately three minutes for the compressor to
start. Note that the outdoor fan may not come on immediately, because it is cycled by
refrigerant pressures.
NOTE: (ComPac
®
II A/C only) To check the system operation under different ambient
conditions, the air temperature and enthalpy sensors must be "tricked". When outdoor
ambient conditions are higher than the control setting, a component cooler aerosol may be
sprayed directly into the enthalpy sensor to simulate low enthalpy conditions, causing the
economizer damper to open.
Alternately, when outdoor conditions are lower than the set point, a source of heat such
as a hair dryer can be directed on the air temperature sensor to simulate warmer
conditions, which will bring on mechanical cooling and start the compressor.
5. To stop cooling, slowly raise the thermostat cooling to a temperature higher
than the ambient.
If the unit fails to operate, refer to the troubleshooting information in Chapter 4.
Follow the same procedure for additional units.
NOTE: Blower Time Delay Relay (BTR) allows the indoor fan to run for approxi-
mately 90 seconds after the compressor is off. This operation provides a small
improvement in system S.E.E.R.
Procedure: (Applies only to units with resistance elements)
1. Raise the heating temperature to a setting which is higher than the ambient temperature.
The fan and electric heat should immediately cycle on.
2. Move the system switch to the "OFF" position. All functions should stop.
NOTE: (ComPac
®
II A/C only) The damper blade should remain closed during the heating
cycle (unless the minimum position potentiometer has been set for constant ventilation A fully
counterclockwise position corresponds to full closure of the damper.
S
TART
-U
P
3.1 C
HECK
-O
UT
OF
C
OOLING
C
YCLE
3.2 C
HECK
-O
UT
OF
H
EATING
C
YCLE
