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Bryant R-22 User Manual

Page 20

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13. Shut off unit power and reconnect fan lead.

14. Remove jumper between DFT and R terminals. Reconnect

defrost-thermostat leads. Failure to remove jumper causes
unit to switch to defrost every 30, 50, or 90 minutes and
remain in defrost for full 10 minutes.

15. Replace control-box cover. Restore power to unit.

If defrost thermostat does not check out following above items or
incorrect calibration is suspected, check for a defective thermostat
as follows.

1. Follow items 1-5 above.

2. Route sensor or probe underneath coil (or other convenient

location) using thermocouple temperature-measuring de-
vice. Attach to liquid line near defrost thermostat. Insulate
for more accurate reading.

3. Turn on power to outdoor unit.

4. Restart unit in heating.

5. Within a few minutes, liquid-line temperature drops within

a range causing defrost-thermostat contacts to close. Tem-
perature range is from 33°F to 27°F. Notice temperature at
which ohmmeter reading goes from

to zero ohms.

Thermostat contacts close at this point.

G

E

W2

14

L

W3

R

Y

O

C

W1

90

50

OF2

OF1

G

C

C

C

R

R

C

Y

O

DFT

HK32FA003/HK32FA006

A88404

OF1

OF2

O

R

T2

Y

TI DFT

C

TEST 30 50 90

W1

O

R

W2

Y

C

CES0110063,

CES0130024

A91444

Fig. 20—Inserting Jumper Wire

G

E

W2

14

L

W3

R

Y

O

C

W1

30 50

OF2 OF1

G

C

C

C

R

R

C

Y

O

DFT

HK32FA003/HK32FA006

A88403

OF1

OF2

O

R

T2

Y

TI DFT

C

TEST 30 50 90

W1

O

R

W2

Y

C

CES0110063,
CES0130024

A91443

Fig. 21—Checking Between C and W2

TABLE 10—DEFROST CONTROL SPEED-UP TIMING SE-

QUENCE FOR CES0110063/CES0130024

PARAMETER

MINIMUM

MAXIMUM

SPEED-UP

(NOMINAL)

30-minute cycle

27

33

7 sec

50-minute cycle

45

55

12 sec

90-minute cycle

81

99

21 sec

10-minute cycle

9

11

2 sec

5 minutes

4.5

5.5

1 sec

—20—