Bryant 551B Pre-Start-Up, START-UP Unit Preparation, II. RETURN-AIR Filters, Internal Wiring

PRE-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 prop- erly tagged.

4.Relieve all pressure from system before touch- ing or disturbing anything inside terminal box if refrigerant leak is suspected around compres- sor 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-wiring and factory-wiring con- nections. Be sure that connections are completed and tight.

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

4.Verify the following:

a.Make sure that condenser-fan blades are correctly positioned in fan orifice. Refer to Condenser-Fan Adjustment section on page 42 for more details.

b.Make sure that air filters are 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.Make sure that the start-up checklist has been performed and filled out.

NOTE: Ensure wiring does not contact any refrigerant tubing.

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 SCREENS

Outdoor-air inlet screens 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.

VI. REFRIGERANT SERVICE PORTS

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

VII. HIGH FLOW VALVES

Two high flow refrigerant valves are located on the compres- sor hot gas and suction tubes. Large black plastic caps dis- tinguish these valves with o-rings located inside the caps. These valves can not be accessed for service in the field. Ensure the plastic caps are in place and tight or the possibil- ity of refrigerant leakage could occur.

VIII. COMPRESSOR ROTATION

On 3-phase units, it is important to be certain the scroll compressor is rotating in the proper direction. To determine whether or not compressor 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 evaporator fan is probably also rotating in the wrong direction.

2.Turn off power to the unit and install lockout tag.

3.Reverse any two of the unit power leads.

4.Turn on power to the unit.

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

NOTE: When the compressor is rotating in the wrong direc- tion, the unit makes an elevated level of noise and does not provide heating or cooling.

CAUTION: Compressor damage will occur if rota- tion is not immediately corrected.

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