Bryant 764A I. Heating Section Start-Upand Adjustments, A. Checking Heating Control Operation

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, 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 con- nections using electronic leak detector, halide torch, or liquid-soap solution. If refrigerant leak is de- tected, see Repairing Refrigerant Leaks section on page 15.

c.Inspect all ®eld- and factory-wiring connections. Be sure that connections are completed and tight.

d.Inspect coil ®ns. If damaged during shipping and han- dling, carefully straighten ®ns with a ®n comb.

4.Verify the following conditions:

a.Make sure that condenser fan blade is correctly po- sitioned in fan ori®ce. Top edge of blade should be 3.125 in. from condenser outlet grille.

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

c.Make sure that condensate drain pan and trap are ®lled with water to ensure proper drainage.

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

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

6.Each unit system has 2 Schrader-type ports, one low- side Schrader ®tting located on the suction line, and one high-side Schrader ®tting located on the compressor dis- charge line. Be sure that caps on the ports are tight.

See Start-Up Checklist in back of book. Unit is now ready for initial start-up.

START-UP

I. HEATING SECTION START-UP AND ADJUSTMENTS

(For units with accessory electric heaters.)

CAUTION: Complete the required procedures given in Pre-Start-Up section on this page before starting unit.

Do not jumper any safety devices when operating the unit.

A. Checking Heating Control Operation

Start and check the unit for proper heating control operation as follows:

1.Turn on unit electrical supply.

2.Set system switch selector at HEAT position and fan switch at AUTO. or ON position. Set heating temperature lever above room temperature.

3.The evaporator fan and ®rst-stage heat will start im- mediately. If unit is equipped with 2-stage heaters, second- stage heat will energize upon a call from W2. Check for heating effect at supply diffusers.

4.After the call for heat has been satis®ed, the evaporator fan will stop. For units equipped with time-delay relay, evaporator fan will stop after a 30-second time delay.

To shut off unit, set system selector switch at OFF position or set heating set point lever below room temperature.

B. Heating Sequence of Operation

When power is supplied to unit, transformer (TRAN) is energized.

With thermostat set to call for heating, sequence of operation is as follows:

On a call for heat, circuit R-W and R-G are made through ®rst-stage thermostat bulb. If accessory electric heaters are used, a relay is energized, bringing on ®rst stage of supple- mental electric heat and fan. When thermostat is satis®ed, contacts open, deenergizing relay (on all units) and time- delay relay (on units equipped with time-delay relay). Heat- ers deenergize, and evaporator fan stops after a 30-second time delay (on units equipped with time-delay relay).

II.COOLING SECTION START-UP AND ADJUSTMENTS

CAUTION: Complete the required procedures given in Pre-Start-Up section, page 11, before starting the unit.

Do not jumper any safety devices when operating the unit.

Do not operate the compressor when the outdoor tem- perature is below 40 F (unless accessory low ambient kit is installed).

Do not rapid-cycle the compressor.

A. Checking Cooling Control Operation

Start and check the unit for proper cooling control operation as follows:

1.Place room thermostat SYSTEM switch in OFF posi- tion. Observe that evaporator-fan motor starts when FAN switch is placed in ON position and shuts down after a 30-second time delay when FAN switch is placed in AUTO. position.

2.Place SYSTEM switch in COOL position and FAN switch in AUTO. position. Set cooling control below room tem- perature. Observe that compressor, condenser fan, and evaporator-fan motors start. Observe that cooling cycle shuts down when control setting is satis®ed. Evaporator- fan motor has off-delay (on units equipped with time- delay relay) of approximately 30 seconds on shutdown.

3.When using an auto. changeover room thermostat, place both SYSTEM and FAN switches in AUTO. positions. Observe that unit operates in Heating mode when tem- perature control is set to ``call for heating'' (above room temperature) and operates in Cooling mode when tem- perature control is set to ``call for cooling'' (below room temperature).

B.Checking and Adjusting Refrigerant Charge

The refrigerant system is fully charged with R-22 refriger- ant, and is tested and factory-sealed.

NOTE: Adjustment of the refrigerant charge is not required unless the unit is suspected of not having the proper R-22 charge. See Refrigerant Charge section on page 16 for fur- ther details.

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