ClimateMaster ACL2120CAZ, Руководство по установке

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Charging
5.4 Initial System
Start-Up: Verifying
Correct Indoor Blower
Motor and Compressor
Rotation.
After the refrigerant charge is weighed in, it is
recommended that electrical power be applied to
both the indoor and outdoor units for a minimum
of 12 hours with the thermostat turned to the
OFF position to give the crankcase heater time to
drive liquid refrigerant from the compressor shell.
After 12 hours, the thermostat may be adjusted
to call for the cooling mode. It is very important
at this point to verify that the indoor blower motor
rotation (3-phase air-handlers) and compressor
rotation are both correct to prevent damage to the
compressor.
• If the 3-phase indoor blower is turning
backwards (blower turning, but no air-flow), shut
the electrical power off to the indoor and outdoor
units and reverse two incoming line voltage leads
to the air-handler. Restore electrical power to the
indoor and outdoor units and verify the indoor
blower motor rotation is correct and air is flowing
through the ductwork.
• Check to make sure the liquid pressure increases
and the suction pressure decreases when the
compressor first starts, indicating the compressor
rotation is correct. If there is no pressure
differential and the compressor is making a loud
rattling sound, shut the electrical power off to
the outdoor unit and reverse two of the incoming
power leads at the outdoor unit contactor.
Restore electrical power to the outdoor unit and
confirm the liquid pressure increases the suction
pressure decreases, and the compressor is
operating at a normal sound level.
Note: The outdoor fan motor is a single phase
motor and will therefore always have the correct
rotation regardless of how the electrical power is
connected to the contactor.
5.5 Verifying Indoor Air-
Flow
Before final refrigerant charge adjustment, the
indoor air-flow must be verified and adjusted if
necessary. Adjust the thermostat set point so
the indoor air-handler or furnace operates in
the cooling air-flow mode. Some air-handlers
and furnaces deliver a different air-flow level for
continuous fan operation, so it is important to verify
the indoor air-flow while the thermostat is set to
operate in the cooling mode. Determine the rated
indoor air-flow by referring to the AHRI Directory,
manufacturer’s specifications, or engineer’s
specification for the matched system. If this
information is not available, 350 - 400 CFM per ton
is a good rule of thumb. Refer to the air-handler
or gas furnace installation and operation manual
for air-flow tables and for adjusting the cooling
mode indoor air-flow. External static pressure will
need to be measured and used for this adjustment.
For furnace/coil combinations, the coil pressure
drop is considered part of the external static
pressure to the furnace. An air velocity meter or
air-flow hood can also give an accurate reading for
indoor air-flow.
5.6 Charging
1) Once the indoor air-flow is verified, operate the
system for a minimum of 15 minutes in the cooling
mode prior to checking pressures and the outdoor
ambient temperature.
IMPORTANT:
Indoor conditions must be within
2°F [1.1°C] of comfort conditions per the building
manager’s preference for final refrigerant charging.
If the indoor temperature is above or below this
range, continue running the system in the cooling
mode or run the furnace or electric heat to bring
the temperature to within this range.
2) Locate the system charging chart on the inside
of the control box cover or in Section 5.7 of this
manual.
3) Note the Outdoor Dry Bulb Temperature, Suction
(Vapor) Pressure, and Liquid Pressure.
4) Find the intersection of the Suction (Vapor)
Pressure on the appropriate Outdoor Ambient
Temperature line and note the Liquid Pressure on
the chart. If the outdoor ambient is between two
of the outdoor ambient lines on the chart, estimate
the liquid pressure as required.
5) If the measured liquid pressure is below the
liquid pressure indicated on the charging chart, add
refrigerant to the system. If the measured liquid
pressure is above the liquid pressure indicated on
the charging chart, remove refrigerant from the
5.0 SYSTEM START-UP & REFRIGERANT CHARGING