CACG/CAHG/CAHJ & CACH/CAHH/CAHK
Air Handlers
• Installation, Operation and Maintenance Manual •
Comfort where it counts
56
P/N 240008108, Rev. G [07/08/10]
Q:
Th
e 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 butt on in.
If the switch was tripped there will be a
click when it resets.
A:
Th
e cassett e 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.
Th
e condensate pump should be checked
for obstruction. Th
e condensate pump
assembly can be removed through the
side access panel. Aft er 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. Th
e 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.
Q:
What causes my indoor unit to freeze-
up?
A:
Air handler freeze up is usually the
symptom of another problem. Th
e Cas-
sett e air handler is equipped with freeze
protection to prevent freeze up from
occurring. If freeze up does occur then
check the following.
Check that the freeze sensor inserted
–
fully and snug in the coil fi ns. If not
another location may need to be
selected. Be careful not to insert the
sensor directly into the coil tube
rather insert the sensor between two
tubes.
Check the indoor air fi lter. It should
–
be clean and free of dirt. A dirty fi lter
will reduce airflow and efficiency.
Also check that the coil is clean. If the
coil is dirty then it should be cleaned
using an appropriate coil cleaner or
mild detergent.
Is the equipment being operated in
–
cooling mode when outdoor tem-
peratures are below 35°F (2°C)? If
it is, then the condenser should be
fitted with low ambient control so
that the proper system pressures are
maintained.
Does the system have the proper
–
refrigerant charge? A system low on
refrigerant can cause air handlers
freeze-up. To check system charge
you will need to contact a qualifi ed
refrigeration service technician.
Refrigerant charge information can
be found in IOM for the outdoor
condensing unit.
Q:
Th
e system has just been installed us-
ing an EMI indoor unit and a non-EMI
condenser. Th
ere is no display and the
unit will not operate.
Frequently Asked Questions