Carrier VECTOR 1800 MT - Page 300

9-7
62-11039
INDICATION/
TROUBLE
POSSIBLE CAUSES
REFERENCE
SECTION
REFRIGERATION (Continued)
9.4.5 Unit Will Not Terminate Heating
Controller improperly set Reset
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Controller malfunction 9.4.9
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Heater termination thermostat remains closed along with
the heat relay
Repair
9.4.6 Defrost Cycle Malfunction
Defrost air switch (DAS) out of calibration 8.25
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A DTT is above 40_F(4.4_C) Cool Box Down
Will not initiate defrost
a
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o
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a
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l
y
Defrost air switch (DAS) defective 8.24 & 8.25
au
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ca
l
l
y
Loose terminal connections Tighten
Air sensing tubes defective or disconnected Check
Microprocessor defective Replace
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Loose terminal connections Tighten
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not
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ate
d
e
f
rost manua
l
l
y
DTT2 is above 40_F(4.4_C) Cool Box Down
Unit has been running less than 15 seconds Try again
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Heater contactor or coil defective Replace
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ates
b
ut
d
oes not
d
e
f
rost
Heater(s) burned out 8.7
F
r
e
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t
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f
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o
s
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Defrost air switch (DAS) out of adjustment 8.24 & 8.25
F
requent
d
e
f
rost
Wet load Normal