Carrier 69NT20-531-300 Manual

A SERVICE OF

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5-5

T -309

CONDITION POSSIBLE CAUSE

REMEDY/

REFERENCE

SECTION

5.14 COMPRESSOR OPERATING IN REVERSE

CAUTION

Allowing the scroll compressor to operate in reverse for more than two minutes will result in internal

compr e ssor damage. Turn the start--stop switch OFF immediately.

Incorrect wiring of compressor

Electrical

Incorrect wiring of compressor contactor(s)

Check

E

l

e

c

t

r

i

c

a

l

Incorrect wiring of current sensor

C

h

e

c

k

5.15 ABNORMAL TEMPERATURES

Discharge temperature sensor drifting high Replace

Failed economizer, TXV or solenoid valve Replace

High discharge temperature

Plugged economizer, TXV or solenoid valve Replace

H

i

g

h

d

i

s

c

h

a

r

g

e

t

e

m

p

e

r

a

t

u

r

e

Loose or insufficiently clamped sensor Replace

Failed liquid injection solenoid valve Replace

L

o

w

s

u

c

t

i

o

n

t

e

m

p

e

r

a

t

u

r

e

Discharge temperature sensor drifting low Replace

L

o

w

suction temperature

Loose or insufficiently clamped sensor Replace

5.16 ABNORMAL CURRENTS

Unit reads abnormal currents Current sensor wiring Check