Instruction manual

McQuay OM 920 45
Keypad/Display Menu Structure
Manual Ctrl is an adjustable item that puts the unit into manual control. Major components of
the unit are turned on and off by this control. The units normal control sequences are
overridden in this state with the exception of all the “fault” alarms and the cooling circuit high
pressure and low pressure alarms.
Supply Fan is an adjustable item that turns on the supply fan.
RF/EF is an adjustable item that turns on the return/exhaust fan.
SAF Spd Cmd is an adjustable item only on VAV units that sets the speed of the supply air
fan.
RF/EF Spd Cmd is an adjustable item for units with VFD on the return/exhaust fans that set
the speed of the return/exhaust fan.
OAD/Econo is an adjustable item which is used to set the economizer damper position.
OAD OpCl is an adjustable item which is used to turn the OA damper output on. This output
is available only on self contained units.
Comp 1 OnOff is an adjustable item that turns on compressor #1.
Comp 2 OnOff is an adjustable item that turns on compressor #2.
Comp 3 OnOff is an adjustable item that turns on compressor #3.
Comp 4 OnOff is an adjustable item that turns on compressor #4.
Comp 5 OnOff is an adjustable item that turns on compressor #5.
Comp 6 OnOff is an adjustable item that turns on compressor #6.
Comp 7 OnOff is an adjustable item that turns on compressor #7.
Comp 8 OnOff is an adjustable item that turns on compressor #8.
CFan Outpt 1 an adjustable item that turns on the condenser fan output #1.
CFan Outpt 2 an adjustable item that turns on the condenser fan output #2.
CFan Outpt 3 an adjustable item that turns on the condenser fan output #3.
Note – Turning on any one of the compressors will automatically turn on the first condenser fan on
the circuit. Other condenser fans must be manually turned on to control the head pressure
of the unit. Refrigerant gauges must be connected to the unit for observation of the head
pressure in the manual control mode of operation. Additional condenser fans must be
turned on to maintain the head pressure.
BP/WR Valve is an adjustable item used to manually drive the bypass/water regulating valve
open and closed.
Manual Control Htg Stg 5= Off Off 4
On
Htg Stg 6= Off Off 4
On
Reheat Valve= 0% 0-100% 4
Reheat Stage= Off Off 4
ERec Wheel= Off Off 4
On
ER Whl Cmd= 0% 0-100% 4
ERBP Dmpr Cl= Off Off 4
On
ERBP Dmpr Op= Off Off 4
On
Cond Wtr Pump= Off Off 4
On
Alm Output= Off Off 4
On
FanOp= Off Off 4
On
Table 39: Manual Control Manual
Menu Display Name Item Display Name Default Setting Range Password Level