Initial Start-Up & Checks; Field Charging; Field Inspection - COMFORT-AIRE CMA18SB-1 Installation, Operation & Maintenance Manual

Horizontal/Side Discharge Condensing Units
Operation of the unit is automatic and will provide
cooling depending on the setting of the thermostat.
IMPORTANT!
All panels must be installed, main power turned
on and the thermostat properly connected before
operating the unit.
1. System check - set thermostat system switch to
"Off" position and fan switch to "Auto" position.
Turn the power supply breaker on.
2. Set the fan switch to "On," blower should
operate.
3. Return the fan switch to "Auto". Blower should
shut off. Set the system switch to "Cool" and
lower thermostat set point to coldest setting.
The compressor, condenser fan, and evaporator
blower should all come on. Cool air will be
supplied after a couple of minutes of run time.
4. Proceed to the "FIELD CHARGING" section of
these instructions.

FIELD CHARGING

to a large extent, on a proper system charge.
Time spent on getting the charge right at start-up
will payoff in the long run. Operating conditions
and indoor and outdoor temperature and humidity
all have an effect on the system pressures and
superheat conditions.
Charge must be added for the interconnecting
tubing. Evaporator coils require thermostatic
expansion valves. These units should be critically
charged to ensure proper performance. Some
systems may require additional charging of
refrigerant, depending on line set lengths.
INITIAL START-UP & CHECKS
FINAL INSPECTION
Review Unit Operation with the homeowner/user.
The pressure/temperature chart can be used as a
reference to ensure performance.
R(oz): Additional refrigerant to be charged
L(ft): The length of the liquid pipe
T(oz): The quantity of the charged refrigerant
per additional foot
oz/ft
12
AITONS EQUIPMENT
0.16 0.32