CACG/CAHG & CACH/CAHH
Air Handlers
• Installation, Operation and Maintenance Manual •
Comfort where it counts
56
P/N 240008108, Rev. B [082509]
Q:
The system has just been installed us-
ing an EMI indoor unit and a non-EMI
condenser. There is no display and the
unit will not operate.
A:
EMI air handlers are manufactured with a
low-voltage transformer installed. When
connecting an EMI evaporator to a non-
EMI condenser, check to ensure that
there is no 24v control transformer in
the outdoor unit. Only one transformer
is required. If both the indoor unit and
outdoor unit contain a transformer, one
must be removed from the system.
Q:
The condenser will not start although
the indoor unit appears normal. What
should I do?
A:
At the indoor thermostat, make sure that
the control is in cooling and the setpoint
temperature is below room temperature.
Next, using a Voltmeter, check for 24V
across the yellow (Y) and brown (C)
wires. If 24V is present then check for
wiring breaks or improper connections
between the indoor and outdoor units.
A:
EMI condensers are equipped with a
manual reset high-pressure switch. It is
located on the high side of the system
usually on back panel above service
valves. To reset, push the red button in.
If the switch was tripped there will be a
click when it resets.
A:
The cassette air handlers are equipped
with an internal condensate pump with a
high level safety switch. If the condensate
reaches a critical level or if power is lost
to the indoor unit, the safety circuit will
open and low Volt power to the con-
denser (terminal “Y1”) will be removed.
The condensate pump should be checked
for obstruction. The condensate pump
assembly can be removed through the
side access panel. After removal, inspect
the drain pan to determine if the con-
densate is not being removed properly
from the unit. Inspect all drain lines to
ensure there is no blockage preventing
condensate removal.
Q:
How long will the fan run?
A:
While the unit is in cooling or heating
and auto fan mode is selected, the fan will
cycle with the call for cooling or heating.
When the room temperature reaches
setpoint temperature, the heat/cool call
is dropped. The fan will then stay on for
an additional 60-second to purge unit
of any residual energy. Placing the fan
selection switch on the wall mounted
thermostat in the ON position will cause
the fan to run continuously regardless of
the set point temperature.
Frequently Asked Questions
