McQuay MDS Series User Manual

Service Manual SM-MDS_(ii) 71
ER55
System error
 High pressure malfunction occur 3 times within 1 hour
- outdoor unit motor broken (cooling)
- outdoor circulating air short (cooling)
- outdoor heat exchanger too dirty (cooling)
- outdoor ball valve not open
- indoor circulating air short (heating)
- indoor heat exchanger too dirty (heating)
- indoor unit filter web blocked (heating)
- indoor unit EXV not turn on properly (heating)
- too much refrigerant
- outdoor unit PCB high pressure output port malfunction
- pressure sensor broken
- pressure switch broken
 Low pressure malfunction occur 3 times within 1 hour
- outdoor ball valve not open
- refrigerant leakage or shortage
- outdoor unit PCB low pressure output port malfunction
- low pressure sensor broken
 Too high discharge temperature occur once
- outdoor unit motor broken (cooling)
- outdoor circulating air short (cooling)
- outdoor heat exchanger too dirty (cooling)
- outdoor unit EXV not turn on properly (heating)
- indoor unit EXV not turn on properly
- refrigerant leakage or shortage
- outdoor ball valve not turns on
 Compressor overload protector shut and occurs 3 times
- too much current flow in the compressor
- compressor overload protector protecting value wrongly set
80
ER56
Discharge temperature
is too high
 Outdoor motor broken (cooling)
 Outdoor circulation air short-circuit (cooling)
 Outdoor heat exchanger too dirty (cooling)
 Outdoor EXV not on properly (heating)
 Indoor EXV not on properly (heating)
 Refrigerant leakage or insufficient
 Outdoor ball valve not open
78
ER59
Ambient temperature is
beyond the limit
 Outdoor ambient temperature exceed running range
- cooling running range 0 – 43ºC
- heating running range -15 – 16 ºC
 Outdoor circulating air short
- Cause outdoor ambient temperature rising to exceed running range when cooling.
- Cause outdoor ambient temperature falling to exceed running range when heating.
84
ER60
Emergency run
 On the premise that part of the indoor unit communication malfunction and either one (or
both) of the following error occurs (unit will shut down):
1. System sub heat <1ºC for 15 minutes
2. TH12 malfunctions
87
ER61
Super heat is beyond
the limit
 Indoor motor not working when cooling
 Indoor EXV opening degree abnormal when cooling
 Outdoor motor not working when heating
 Outdoor EXV opening degree abnormal when heating
 Low pressure sensor abnormal
 Refrigerant over charged
86
6

McQuay MDS Series Specifications

General

Brand	McQuay
Model	MDS Series
Category	Compressor
Language	English