Carrier 48HJD005-007 specifications Pre-Start-Up

PRE-START-UP

Failure to observe the following warnings could result in serious personal injury:

1.Follow recognized safety practices and wear protec- tive goggles when checking or servicing refrigerant system.

2.Do not operate compressor or provide any electric power to unit unless compressor terminal cover is in place and secured.

3.Do not remove compressor terminal cover until all electrical sources are disconnected.

4.Relieve all pressure from system before touching or disturbing anything inside terminal box if refrigerant leak is suspected around compressor terminals.

5.Never attempt to repair soldered connection while re- frigerant system is under pressure.

6.Do not use torch to remove any component. System contains oil and refrigerant under pressure. To remove a component, wear protective goggles and proceed as follows:

a.Shut off electrical power and then gas to unit.

b.Reclaim refrigerant to relieve all pressure from system using both high- and low-pressure ports.

c.Cut component connection tubing with tubing cutter and remove component from unit.

d.Carefully unsweat remaining tubing stubs when necessary. Oil can ignite when exposed to torch flame.

Proceed as follows to inspect and prepare the unit for initial start-up:

1.Remove all access panels.

2.Read and follow instructions on all WARNING, CAU- TION, and INFORMATION labels attached to, or shipped with, unit.

3.Make the following inspections:

a.Inspect for shipping and handling damages such as broken lines, loose parts, or disconnected wires, etc.

b.Inspect for oil at all refrigerant tubing connections and on unit base. Detecting oil generally indicates a refrigerant leak. Leak-test all refrigerant tubing connections using electronic leak detector, halide torch, or liquid-soap solution.

c.Inspect all field- and factory-wiring connections. Be sure that connections are completed and tight. Be sure that wires are not in contact with refriger- ant tubing or sharp edges.

d.Inspect coil fins. If damaged during shipping and handling, carefully straighten fins with a fin comb.

4.Verify the following conditions:

a.Make sure that condenser-fan blade are correctly positioned in fan orifice. See Condenser-Fan Adjustment section on page 34 for more details.

b.Make sure that air filter(s) is in place.

c.Make sure that condensate drain trap is filled with water to ensure proper drainage.

d.Make sure that all tools and miscellaneous loose parts have been removed.

START-UP

Unit Preparation — Make sure that unit has been in- stalled in accordance with installation instructions and applica- ble codes.

Return-Air Filters — Make sure correct filters are in- stalled in unit (see Table 1). Do not operate unit without return- air filters.

Outdoor-Air Inlet Screens — Outdoor-air inlet screen must be in place before operating unit.

Compressor Mounting — Compressors are internally spring mounted. Do not loosen or remove compressor hold- down bolts.

Internal Wiring — Check all electrical connections in unit control boxes. Tighten as required.

Refrigerant Service Ports — Each unit system has 3 Schrader-type service ports: one on the suction line, one on the liquid line, and one on the compressor discharge line. Be sure that caps on the ports are tight. Two additional Schrader valves are located under the high-pressure and low-pressure switches, respectively.

HIGH FLOW REFRIGERANT VALVES — Two high flow valves are located on the hot gas tube coming out of the com- pressor and the suction tube going into the compressor. Large black plastic caps identify these valves. These valves have O-rings inside which screw the cap onto a brass body to pre- vent leaks. No field access to these valves is available at this time. Ensure the plastic caps remain on the valves and are tight or the possibility of refrigerant leakage could occur.

Compressor Rotation — On 3-phase units with scroll compressors, it is important to be certain compressor is rotating in the proper direction. To determine whether or not compres- sor is rotating in the proper direction:

1.Connect service gages to suction and discharge pressure fittings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pres- sure should rise, as is normal on any start-up.

If the suction pressure does not drop and the discharge pres- sure does not rise to normal levels:

1.Note that the evaporator fan (006 and 007 only) is proba- bly also rotating in the wrong direction.

2.Turn off power to the unit, tag disconnect.

3.Reverse any two of the unit power leads.

4.Reenergize to the compressor. Check pressures.

The suction and discharge pressure levels should now move to their normal start-up levels.

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