Bryant 698B B. One Minute Speed Change Time Delay, C. Heating Operation, Viewfrom Top of Base Pan

Models: 698B

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B. ONE MINUTE SPEED CHANGE TIME DELAY

NOTE: When two-speed unit is operating in low-capacity cool- ing, system vapor (suction) pressure will be higher than a standard single-speed system or high-speed operation. This normal opera- tion is due to the reduced capacity operating with typically larger indoor and outdoor coils.

B. ONE MINUTE SPEED CHANGE TIME DELAY

When compressor changes speeds from high to low or low to high, there is a 1-minute time delay before compressor restarts. The outdoor fan motor remains running.

C. HEATING OPERATION

This product utilizes a 3-stage heating indoor thermostat. With a call for first stage heating (Y1), the outdoor fan and low capacity compressor are energized. If low capacity cannot satisfy heating demand, high capacity is energized (Y1 and Y2) by the second stage of the indoor thermostat. Auxiliary or back up heat is controlled by third stage (W1). After second stage of heat is satisfied, the unit returns to low capacity operation until first stage is satisfied or until second stage is required again. When both one stage and two stage heating are satisfied, the compressor will shut off. See thermostat Installation Instructions for more staging information.

NOTE: If unit has not operated within the past 12 hr or following a unit power-up, upon the next thermostat high- or low-speed demand, unit operates for a minimum of 5 minutes on high speed.

THERMISTOR CURVE

 

90

(KOHMS)

80

70

 

 

60

RESISTANCE

50

20

 

40

 

30

10

0

0

20

40

60

80

100

120

TEMPERATURE (DEG. F)

A91431

Fig. 16—Resistance Values Versus Temperature

Control Box

Side of Unit

THERMISTOR PLACED UNDERNEATH BASE PAN (ATTACHED TO BASE PAN WITH ADHESIVE)

A02218

Fig. 17—View from Top of Base Pan

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D. STATUS FUNCTION LIGHTS

A system control STATUS function light is located on the outdoor unit control board. (See Fig. 15). The STATUS light provides signals for several system operations. See Table 4 for codes and definitions. Table 4 also provides the order of signal importance. NOTE: Only one code will be displayed on the outdoor unit control board (the most recent, with the highest priority).

E. FACTORY DEFAULTS

Factory defaults have been provided in the event of failure of outdoor air thermistor and/or outdoor coil thermistor. Refer to Table 6 for default and function.

F. COMPRESSOR OPERATION

When the compressor operates in two-capacity operation, the motor rotates clockwise. Both the lower and upper pistons are eccentric with the rotating crankshaft, and both compress refrig- erant. When the compressor operates in single capacity the motor reverses direction (rotates counterclockwise). The lower piston becomes idle and the upper piston compresses refrigerant. During single-capacity operation the “start” and “run” windings are reversed.

G. CRANKCASE HEATER OPERATION

The two-speed control energizes the compressor crankcase heater during unit’s off cycle.

H. OUTDOOR FAN MOTOR OPERATION

The two-speed control energizes outdoor fan any time compressor is operating. The outdoor fan remains energized during the 1-minute speed change time delay and if a pressure switch or compressor overload should trip. Outdoor fan motor will continue to operate for one minute after the compressor shuts off when the outdoor ambient is greater than 100°F.

TABLE 4—LED CONTROL FUNCTION LIGHT CODE

CODE

DEFINITION

*

Constant flash

No demand

10

No pause

Stand by

 

1 flash

Low-speed operation

9

w/pause

 

 

2 flashes

High-speed operation

8

w/pause

 

 

3 flashes

Outdoor ambient thermistor failure

7

w/pause

 

 

4 flashes

Outdoor coil thermistor failure

6

w/pause

 

 

3 flashes

 

 

pause

Thermistor out of range†

5

4 flashes

 

 

5 flashes

 

 

pause

Low pressure switch trip

4

1 flash

 

 

5 flashes

 

 

w/pause

High pressure switch trip

3

2 flashes

 

 

6 flashes

Compressor VC/VH trip

2

w/pause

 

 

Constant light

 

 

No pause

Board failure

1

No flash

 

 

*Function light signal order of importance in case of multiple signal request; 1 is most important.

† Check both thermistors to determine which is faulty.

TABLE 5—DEFROST DIP SWITCH SETTINGS

TIME

DIP SWITCH #1

DIP SWITCH #2

30

up

down

60

down

up

90

down

down

120

up

up

 

 

 

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Bryant 698B B. One Minute Speed Change Time Delay, C. Heating Operation, ResistanceValues Versus Temperature