Operating Theory; Magnum+ Operating Mode Function Chart - Trane Thermo King Magnum Plus Operator's Manual

OPERATING THEORY

OPERATING THEORY
Chill Loads
Setpoints at -9.9 C
(14.4 F) and Above
Cool w/Mod Heat
• •
1
•
1
• •
•
•
•
•
• •
5
1 Setpoint temperature and controlling mode
setting determine the evaporator fan speed:
Normal Operation :
Chill Loads — High
or low speed fans; Frozen Loads — Low speed
fans or no fans.
2 Vapor injection valve:
Chill, Frozen or Power Limit Mode:
When the cool capacity is 100 percent.
26

MAGNUM+ Operating Mode Function Chart

Frozen Loads
Setpoints at -10 C
(14 F) and Below
Defrost Cool Null
• •
1
• •
1
• •
•
•
•
•
•
4
•
Compressor High Temperature
Protection:
temperature exceeds 138 C (280 F).
Condenser fan pulses on and off on a 30
3
second duty cycle to maintain a minimum
condenser temperature:
Chill Loads:
minimum 30 C (86 F) condenser temperature.
Defrost
Evaporator Fans High Speed
Evaporator Fans Low Speed
• Evaporator Fans Off
Proportional-integral Derivative (Supply Air) Control
Return Air Sensor Control
• Evaporator Coil Sensor Control
Compressor On
Compressor Vapor Injection On (valve energized)
Condenser Fan On
Digital Control Valve Modulating (energized)
• Electric Heaters Pulsing or On (energized)
When the compressor discharge
Controller maintains a
Unit Function
1
1
1
2
3
4
5
Frozen Loads:
Controller maintains a
minimum 20 C (68 F) condenser temperature.
4 Digital Control valve modulates: Chill Loads
— whenever the unit is in a Cooling mode;
Power Limit — whenever the unit is in Power
Limit mode.