EMI CAC_36, Инструкция по установке, эксплуатации и обслуживанию

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Cassette Air Handler
42
TROUBLESHOOTINg pROCEdURE
Continued
frequently Asked questions
q: The system has just been installed using
an EMi indoor unit and a non-EMi con-
denser and the unit will not operate.
A:
The Cassette air handler is manufactured
with a low Volt transformer installed.
EMI outdoor condensers are manufac
-
tured without a low Volt transformer.
When connecting an EMI air handlers to
a non-EMI condenser, check to ensure
that there is a 24V control transformer in
either in the indoor unit or 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 set
-
point temperature is below room tem
-
perature. 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 connec
-
tions between the indoor and outdoor
units.
A:
Some EMI condensers are equipped with
a manual reset high-pressure switch. It is
located on the high side of the system
usually on the discharge line of the com
-
pressor. To reset, simply 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 condens
-
er (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 conden
-
sate is not being removed properly from
the unit. Inspect all drain lines to ensure
there is no blockage preventing conden
-
sate 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 heat
-
ing. When the room temperature reach
-
es setpoint temperature, the heat/cool
call is dropped. The fan will then stay on
for an additional 60 sec. to purge unit of
any residual energy.
Placing the fan selection switch on the
wall mounted thermostat in the ON posi
-
tion will cause the fan to run continuously
regardless of the set point temperature
.
q: What causes my indoor unit to freeze-up?
A:
Air handlers freeze up is usually the
symptom of another problem. The Cas
-
sette 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 fins. If not an
-
other location may need to be select
-
ed. Be careful not to insert the sensor
directly into the coil tube rather insert
the sensor between two tubes.
• Check the indoor air filter. It should
be clean and free of dirt. A dirty filter
will reduce airflow and efficiency. Also
check that the coil is clean. If the coil
is dirty then it should be cleaned us
-
ing an appropriate coil cleaner or mild
detergent.
• Is the equipment being operated in cool
-
ing mode when outdoor temperatures
are below 65°F (18°C)? If it is, then the
condenser should be fitted with low am
-
bient control so that the proper system
pressures are maintained.