Bryant 548D Pre-Start-Up, Start-Up I. Unit Preparation, Ii. Return Air Filters

Models: 548D

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PRE-START-UP

PRE-START-UP

START-UP WARNING: Failure to observe the following warn- ings could result in serious personal injury:

1.Follow recognized safety practices and wear protective goggles when checking or servicing refrigerant system.

2.Do not operate compressor or provide any elec- tric 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 and tagged.

4.Relieve all pressure from system before touch- ing or disturbing anything inside compressor terminal box if refrigerant leak is suspected around compressor terminals. Use accepted methods to recover refrigerant.

5.Never attempt to repair soldered connection while refrigerant system is under pressure.

6.Do not use torch to remove any component. Sys- tem contains oil and refrigerant under pres- sure. To remove a component, wear protective goggles and proceed as follows:

a.Shut off electrical power to unit and install lockout tag.

b.Relieve all pressure from system using both high- and low-pressure ports. Use accepted methods to recover refrigerant.

c.Cut component connection tubing with tub- ing 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.

b.Inspect for oil at all refrigerant tubing connec- tions and on unit base. Detecting oil generally indicates a refrigerant leak. Leak-test all refrig- erant 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. Ensure electrical wiring does not come into contact with refrigerant 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 outdoor-fan blades are correctly positioned in fan orifice. Refer to Outdoor Fan Adjustment section on page 32 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.

e.Ensure belt and blower pulley are properly aligned and at correct tension.

START-UP

I. UNIT PREPARATION

Make sure that unit has been installed in accordance with these installation instructions and applicable codes.

II. RETURN AIR FILTERS

Make sure correct filters are installed in unit (see Table 1). Do not operate unit without return-air filters.

III. OUTDOOR-AIR INLET SCREEN

Outdoor-air inlet screen must be in place before operating unit.

IV. COMPRESSOR MOUNTING

Compressors are internally spring mounted. Do not loosen or remove compressor holddown bolts.

V. INTERNAL WIRING

Check all electrical connections in unit control boxes; tighten as required. Ensure wiring does not come into direct contact with refrigerant tubing or sharp edges.

VI. REFRIGERANT SERVICE PORTS

Each refrigerant system has 4 Schrader-type service gage ports: One on the suction line, one on the cooling mode liquid line, and 2 on the compressor discharge line. Be sure that caps on the ports are tight.

VII. HIGH FLOW VALVES

Located on the compressor hot gas and suction tubes are High Flow Valves. Large black plastic caps distinguish these valves with O-rings located inside the caps. These valves cannot be accessed for service in the field. Ensure the plastic caps are in place and tight or the possibility of refrigerant leakage could occur.

VIII. COMPRESSOR ROTATION

It is important to be certain the scroll compressor is rotating in the proper direction. To determine whether or not com- pressor is rotating in the proper direction:

1.Connect service gages to suction and discharge pres- sure fittings.

2.Energize the compressor.

3.The suction pressure should drop and the discharge pressure 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 indoor fan is probably also rotating in the wrong direction.

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

3.Reverse any two of the unit power leads.

4.Turn on power to the unit. Reenergize compressor.

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

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Bryant 548D Pre-Start-Up, Start-Up I. Unit Preparation, Ii. Return Air Filters, Iii. Outdoor-Airinlet Screen