McQuay MDB075B, Manual

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3. Auto Mode Selection
SW5(dip 5)
a. Auto mode off off
b. Auto mode on on
Note : Factory preset : SW5 = off ~ auto mode off
4. Stage Differential Temperature
Differential temperature is the temperature difference between turning on or off 1 compressor to another
compressor in thermostat cycle.
The stage differential temperature can be selected from the range shown below :
Dip switch 3 Dip switch 4
a. Default off off
b. 0.5
°
C on off
c. 1.0
°
C off on
d. 1.5
°
C on on
note that 1.5
°
C only valid for 2 and 3 compressors model. For 4 compressors model, maximum allowed is
1.0
°
C.
The default differential temperature is base on number of compressor model, the setting is as below :
Model Diff. Temperature
1 compressor Not applicable
2 compressor 1.5
°
C
3 compressor 1.0
°
C
4 compressors 0.5
°
C
5. Hot Keep Option
Dip switch 6
a. Fan off off
b. Fan on on
6. Operating Modes
The system has 4 operating modes to select with respect to each model selection:
Model Auto Cool Heat Fan
SQCn - X - X
SQHnh - X X X (Dip switch 5 = off)
SQHnh X X X X (Dip switch 5 = on)
Where x denotes modes available
n = number of compressor(s)
h = number of heater(s)
7. Last Memory Functions
The power up settings for either with or without the last memory backup is based on the JH1 setting.
JH1 Setting
a. Last memory backup JH1 Plugged
b. Without last memory backup JH1 Removed