Bryant Condenser-FanAdjustment, EconoMi$erIV Adjustment, RefrigerantCharge, 551B,C, No Charge

Models: 551B

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Step 3 —Condenser-Fan Adjustment

Table 34—Perfect Humidity Adaptive Dehumidification System Sequence of Operation and

System Response — Single Compressor Unit (551C 024-060, 551B 036-072)

THERMOSTAT INPUT

ECONOMIZER FUNCTION

 

551B,C UNIT OPERATION

H

Y1

Y2

OAT. < Economizer Set Point

Economizer

Comp. 1

Subcooling Mode

Hot Gas Reheat Mode

Off

 

Normal Operation

 

On

On

On

No

Off

On

Yes

No

On

On

Off

No

Off

On

Yes

No

On

On

On

Yes

On

On

Yes

No

On

On

Off

Yes

On

On

No

Yes

On

Off

Off

No

Off

On

No

Yes

NOTE: On a thermostat call for W1, all cooling and dehumidification will be off.

LEGEND

OAT --- Outdoor Air Temperature

551B,C

Step 3 Condenser-Fan Adjustment

Shut off unit power supply. Remove condenser-fan assembly (grille, motor, motor cover, and fan) and loosen fan hub setscrews. Adjust fan height as shown in Fig. 50. Tighten setscrews and replace condenser-fan assembly.

 

UNIT

FAN HEIGHT (in.) - A

 

 

024-060 and 072 (208/230 v)

2.75

 

 

072 (460 v)

3.50

 

 

 

 

 

C06138

Fig. 48 ---Condenser-Fan Adjustment

Step 4 EconoMi$er IV Adjustment

Refer to Optional EconoMi$er IV section.

Step 5 Refrigerant Charge

Amount of refrigerant charge is listed on unit nameplate (also refer to Table 1). Refer to HVAC Servicing Procedures literature available at your local distributor and the following procedures.

Unit panels must be in place when unit is operating during charging procedure. Unit must operate a minimum of 10 minutes before checking or adjusting refrigerant charge.

No Charge

Use standard evacuating techniques. After evacuating system to 500 microns, weigh in the specified amount of refrigerant. (Refer to Table 1 and unit information plate.)

Low Charge Cooling

Using Cooling Charging Charts, Fig. 49-52, vary refrigerant until the conditions of the charts are met. Note the charging charts are different from type normally used. Charts are based on charging the units to the correct superheat for the various operating conditions. Accurate pressure gauge and temperature sensing device are required. Connect the pressure gauge to the service port on the suction line. Mount the temperature sensing device on the suction line and insulate it so that outdoor ambient temperature does not affect the reading. Indoor-air cfm must be within the normal operating range of the unit. An accurate superheat, thermocouple-type or thermistor-type thermometer, and a gauge manifold are required when using the superheat charging method for evaluating the unit charge. Do not use mercury or small dial-type thermometers because they are not adequate for this type of measurement.

C06139

Fig. 49 ---Cooling Charging Chart,

Standard 551B 036

Perfect HumiditySystem Charging

The system charge for units with the Perfect Humidity adaptive dehumidification system is greater than that of the standard unit alone. The charge for units with this option is indicated on the unit nameplate drawing. Also refer to Fig. 53-56. To charge systems using the Perfect Humidity adaptive dehumidification system, fully evacuate, recover, and recharge the system to the nameplate specified charge level. To check or adjust refrigerant charge on systems using the Perfect Humidity adaptive dehumidification system, charge per Fig. 53-56.

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Bryant 551C Condenser-FanAdjustment, EconoMi$erIV Adjustment, RefrigerantCharge, 551B,C, No Charge, Low Charge Cooling