Carrier T--298 Section Service and Maintenance, Preventative Maintenance, Service -- General

SECTION 3

SERVICE AND MAINTENANCE

3.1 PREVENTATIVE MAINTENANCE

Cleaning--Clean evaporator coil and condenser coil. Hold flashlight behind coil to see if all spaces are clear. Dust accumulation obstructs or reduces airflow and results in loss of cooling capacity. Both coils may be vacuumed when dry. Coils may also be brushed with a stiff brush and then blown out with compressed air.

Thoroughly clean base pan, motors, fan wheels, and other components.

Clean cover and ceiling grill. Mild detergents reduce electrostatic charges on plastic sections of the grill and are good cleaners.

CAUTION

Do not use carbon tetrachloride, solvents, or waxes containing solvents to clean plas- tic sections.

Painting--Paint any parts that show evidence of rust with a good rust--prevention paint.

Wiring--Check all wiring for deterioration and all electrical contacts for tightness or corrosion.

Mounting--Make sure unit is secure on roof according to installation instructions provided in Owner’s Guide. Check fans to insure that they are correctly positioned in the center of the orifice, and tight on the shaft.

Leaks--Check any connections that show evidence of oil or leaks. When unit is properly installed (refer to Owner’s Guide) check gaskets for possible air leakage.

Controls--Check unit to ensure all controls are functioning correctly and unit operation is normal. Vibrations can cause unwanted noise.

NOTE

Check to ensure that piping is not vibrating against side of the unit.

NOTE

For proper cleaning and flushing, use a UL approved refrigerant recovery/recycling system.

NOTE

Refrigerant removal must always include recovering the refrigerant, not allowing it to escape to the atmosphere.

WARNING

Before working on the unit be sure to first disconnect all electric power to the unit to avoid the possibility of electrical shock and personal injury. Before disconnecting, dis- charge capacitors by shorting across the capacitors terminals (Refer to paragraph 3.5.8)

WARNING

Shield coils with cardboard to protect hands against injury from sharp metal edges when removing compressor and oth- er components.

3.3 CEILING UNIT -- FREE BLOW SYSTEMS 3.3.1 Filter Removal

The filters (Figure 3-1) are located in the ceiling grill. To remove the filters, do the following:

a. Grasp the edge of the filter at recess in the end of the ceiling grill.

b. Pull filter completely out of the filter slot.

c. Vacuum filter or wash filter in luke--warm water. Shake off excess water and dry thoroughly.

d. Replace filter by sliding the filter into the filter slot in the ceiling grill until the filter frame is flush with the in- terior grill.

Filters

Figure 3-1 Filter Removal -- Free Blow

3.3.2 Ceiling Grill Removal

To remove the ceiling grill (Figure 3-2) do the following:

3.2 SERVICE -- GENERAL

General Notes—These Service Instructions are provided to assist the trained and qualified Carrier service technician in repairing or replacing components of the AirV units.

a. Before working on unit place the master switch in the OFF position and disconnect all electrical power.

b. Remove 4 screws located on the ceiling grill, making sure to support the weight of the grill.

c. Lower the ceiling grill from the ceiling panel.

3-1 T--298