McQuay MDS Series User Manual

70 Service Manual SM-MDS_(ii)
6.5 Outdoor Error Code for MDS-M PCB
Error
Code
Description
Possible Causes
Page
R22
Wrong combination of
PCB and software
 PCB hardware is designed for R22 but software for R410A unit is installed into it.
88
R410
Wrong combination of
PCB and software
 PCB hardware is designed for R410A but software for R22 unit is installed into it.
88
ERSE
Wrong dipswitch setting
 Outdoor dipswitch setting wrong
 Outdoor model dipswitch setting wrong
89
EC00
-
EC47
00# - 47# indoor unit
communication failure
 Indoor 00# - 47# and outdoor communication wire broken
 Indoor 00# - 47# and outdoor communication wire loose
 Indoor 00# - 47# and outdoor communication wire A B reverse
 Indoor 00# - 47# and outdoor jump wire not correct, still on update status
 Indoor 00# - 47# and outdoor PCB program not compatible
 Indoor 00# - 47# and outdoor PCB abnormal
76
ER48
Digital compressor
overload
 Digital compressor operating current too high, overload protector OL4 on
77
ER49
Fixed compressor 1
overload
 Fixed compressor 1 operating current too high, overload protector OL1 on
ER50
Fixed compressor 2
overload
 Fixed compressor 2 operating current too high, overload protector OL2 on
ER51
Fix compressor 3
overload
 Fixed compressor 3 operating current too high, overload protector OL3 on
ER52
Discharge pressure too
high
 Outdoor motor broken (cooling)
 Outdoor circulating air short-circuit (cooling)
 Outdoor heat exchanger too dirty (cooling)
 Outdoor ball valve not open
 Indoor circulating air short-circuit (heating)
 Indoor heat exchanger too dirty (heating)
 Indoor unit filter blocked by dirt (heating)
 Indoor EXV not on properly (heating)
 Refrigerant over charged
 Outdoor PCB high pressure output port abnormal
 Pressure sensor broken
 Pressure switch broken
78
ER53
Suction pressure is too
low
 Outdoor ball valve not open
 Outdoor heat exchanger efficiency too low when heating
 Outdoor motor run abnormally when heating
 Refrigerant leakage or insufficient
 Outdoor PCB low pressure output port abnormal
 Low pressure sensor broken
ER54
Outdoor unit’s IC error
 Outdoor PCB chip read faultily at the very beginning when power on
 Outdoor PCB chip broken
82
6

McQuay MDS Series Specifications

General

Brand	McQuay
Model	MDS Series
Category	Compressor
Language	English