22
IMPORTANT
: Three--phase, scroll compressor units are
direction--oriented. These units must be checked to ensure proper
compressor 3--phase power lead orientation. If not corrected
within 5 minutes, the internal protector shuts off the compressor.
The 3--phase power leads to the unit must be reversed to correct
rotation. When turning backwards, scroll compressors emit
elevated noise levels, and the difference between compressor
suction and discharge pressures may be dramatically lower than
normal.
CHECKING AND ADJUSTING REFRIGERANT
CHARGE
The refrigerant system is fully charged with R--410A refrigerant,
tested, and factory--sealed.
NOTE
: Adjustment of the refrigerant charge is not required
unless the unit is suspected of not having the proper R--410A
charge.
An accurate superheat, thermocouple-- or thermistor--type
thermometer, a sling psychrometer, and a gauge manifold are
required when using the superheat charging method for
evaluating the unit charge. Do not use mercury or small dial--type
thermometers because they are not adequate for this type of
measurement.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in unit damage.
When evaluating the refrigerant charge, an indicated
adjustment to the specified factory charge must always be very
minimal. If a substantial adjustment is indicated, an abnormal
condition exists somewhere in the cooling system, such as
insufficient airflow across either coil or both coils.
!
CAUTION
To Use Cooling Charging Charts
Take the liquid line temperature and read the manifold pressure
gauges. Refer to the chart (See Fig. 20) to determine what the
liquid line temperature should be.
NOTE
: If the problem causing the inaccurate readings is a
refrigerant leak, refer to the Check for Refrigerant Leaks section.
INDOOR AIRFLOW AND AIRFLOW ADJUSTMENTS
For cooling operation, the recommended airflow is 350 to 450
cfm for each 12,000 Btuh of rated cooling capacity. For heating
operation, the airflow must produce a temperature rise that falls
within the range stamped on the unit rating plate. Table 4 shows
the temperature rise at various airflow rates. Table 7 & 8 show
cooling airflows and Table 9 & 10 show heating airflows at the
selection pin ranges (depending on external static pressure). Refer
to these tables to determine the airflow for the system being
installed.
NOTE
: Be sure that all supply-- and return--air grilles are open,
free from obstructions, and adjusted properly.
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
Before making any indoor wiring adjustments, shut off gas
supply. Then disconnect electrical power to the unit.
!
WARNING
Airflow can be changed by changing the selection pins on the
Easy Select circuit board.
MAINTENANCE
To ensure continuing high performance and to minimize the
possibility of premature equipment failure, periodic maintenance
must be performed on this equipment. This combination
heating/cooling unit should be inspected at least once each year
by a qualified service person. To troubleshoot cooling or heating
of units, refer to Tables 12, 13 and 14.
NOTE
: Consult your local dealer about the availability of a
maintenance contract.
PERSONAL INJURY AND UNIT DAMAGE HAZARD
Failure to follow this warning could result in personal injury
or death and unit component damage.
The ability to properly perform maintenance on this
equipment requires certain expertise, mechanical skills, tools
and equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment, other than those
procedures recommended in the Owner’s Manual.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow these warnings could result in personal
injury or death:
1. Turn off electrical power to the unit before performing
any maintenance or service on this unit.
2. Use extreme caution when removing panels and parts.
3. Never place anything combustible either on or in contact
with the unit.
4. Should overheting occur or the gas supply fail to shut
off, turn off external main manual gas valve to the unit.
Then shut off electrical supply.
!
WARNING
UNIT OPERATION HAZARD
Failure to follow this caution may result in improper
operation.
Errors made when reconnecting wires may cause improper
and dangerous operation. Label all wires prior to
disconnecting when servicing.
CAUTION
!
The minimum maintenance requirements for this equipment are
as follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary. Certain geographical locations may require
more frequent inspections.
2. Inspect indoor coil, outdoor coil, drain pan, and
condensate drain each cooling season for cleanliness.
Clean when necessary.
3. Inspect blower motor and wheel for cleanliness at the
beginning of each heating and cooling season. Clean when
necessary. For first heating and cooling season, inspect
blower wheel bi--monthly to determine proper cleaning
frequency.
4. Check electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
when necessary.
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