Carrier DesertMaster 50TJM, Эксплуатация и обслуживание, Страница: 18 / 28

4.5 – Belt Tension Adjustment
To adjust belt tension:
1. Loosen fan motor bolts.
2. Adjust belt tension by sliding the motor on the mounting base.
3. Tighten nuts.
4. Adjust bolts and nut on mounting plate to secure motor in fixed position.
4.6 – Condenser-Fan Adjustment
1. Shut off unit power supply.
2. Remove fan top-grille assembly and loosen fan hub screws.
3. Adjust fan height on unit, using a straightedge placed across the fan orifice.
4. Tighten setscrews
Fig. 9 Condenser - Fan Adjustment
4.7 – Refrigerant Charge
Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to Carrier GTAC II; Module 5;
Charging, Recovery, Recycling, and Reclamation section for charging methods and procedures. Unit panels must be
in place when unit is operating during charging procedure.
NOTE: Do not use recycled refrigerant as it may contain contaminants.
NO CHARGE — Use standard evacuating techniques. After evacuating system, weight in the specified amount of
refrigerant (refer to Table 1).
LOW CHARGE COOLING — Using cooling charging chart (see Fig. 10 to 13 according to the size of the unit) Add
or remove refrigerant until conditions of the chart are met. Note that charging chart is different from those normally
used. An accurate pressure gage and temperature-sensing device is required. Charging is accomplished by
ensuring the proper amount of liquid sub-cooling. Measure liquid line pressure at the liquid line service valve using
pressure gage.
Connect temperature sensing device to the liquid line near the liquid line service valve and insulate it so that outdoor
ambient temperature does not affect reading.
TO USE THE COOLING CHARGING CHART — Use the above temperature and pressure readings, and find the
intersection point on the cooling charging chart. If intersection point on chart is above line, add refrigerant. If
intersection point on chart is below line, carefully recover some of the charge. Recheck suction pressure as charge
is adjusted.
NOTE: Indoor-air CFM must be within normal operating range of unit. All outdoor fans must be operating.
4.8 – Protective Devices
COMPRESSOR PROTECTION – Each compressor is internally protected against over temperature.
Compressor Lockout — If any of the safeties (high-pressure, low-pressure, compressor internal thermostat, external
compressor thermal overload) trip, the CLO (compressor lockout) will lock the compressors off.
To reset, manually move the thermostat setting.
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