Carrier MMY-MAP0724FT9UL Service Manual page 150

Check code
Main Outdoor 7-segment display
remote
Check Sub-code
controller
code
P18 P18 —
Detected
outdoor unit No.
* Display of
header unit only
P19 P19
Location
of
Description
detection
I/F Discharge
temperature TD3
error
I/F 4-way valve
reversing error
Error detection
System status
condition(s)
All stop Discharge temperature (TD3)
exceeds 239˚F (115˚C).
All stop Abnormal refrigerating cycle
data is collected during all
heating operation.
– 150 –
Check items (locations)
• Check outdoor service valves
(discharge gas side, suction
gas side, liquid side) to
confirm full opening.
• Check outdoor PMVs
(PMV1, 2, 4) for clogging.
• Check resistance
characteristics of TD3 sensor.
• Check for defect in 4-way
valve.
• Check SV4 circuit for
leakage.
• Check SV4 circuit (for wiring
or installation error involving
SV41, SV42 and SV43).
• Check SV5 valve circuit
leakage.
• Check SV6 circuit. (Clogging,
valve operation error)
• Check mispiping of discharge
gas/suction gas main pipes.
• Check Cool/Heat FS unit.
Check SVD valve, SVS valve
leakage.
(Check SVDD valve, SVSS
valve leakage.)
Connecting piping to FS unit
Mispiping of (discharge gas/
suction gas)
Check wiring between FS unit
and indoor unit, connection of
connectors.
Check miswiring of SVS/SVD
valve.
• It is necessary to check all the
outdoor units in the identical
refrigerant line.
• Check for defect in main body
of 4-way valve.
• Check for coil defect in 4-way
valve and loose connection of
its connector.
• Check clogging in 4-way valve
capillary
• Check resistance
characteristics of TS1 and
TE1 sensors.
• Check output voltage
characteristics of Pd and Ps
pressure sensors.
• Check for wiring error
involving TE1 and TL sensors.
• Check Cool/Heat FS unit.
Check SVD valve, SVS valve
leakage.
(Check SVDD valve, AVSS
valve leakage.)
Connecting piping of FS unit
Mispiping of (Discharge gas/
suction gas)
SV14 valve body error
(in heating operation)
SV 14valve coil error,
Connector connection check
(in heating operation)