Midea MC-SU60-RN1L Service Manual

Aqua Tempo Super II
201709 29
Part 3
- Control
7 Special Control
7.1 Outdoor Unit Duty Cycling
In systems with multiple outdoor units, outdoor unit duty cycling is used to balance the compressor running time.
Outdoor unit duty cycling occurs whenever all the outdoor units stop running (either because the leaving water set
temperature has been reached or because a master unit error has occurred):
 When the outdoor units are powered on for the first time, if there is a load requirement, the units turn on, starting
with the master unit. As the leaving water temperature approaches its set temperature, units shut down in succession,
starting with the unit with the highest address. Once the set temperature has been reached, the master unit shuts
down.
 The next time a load requirement exists (or, following a master unit error), the units turn on, starting with the unit
with the highest address. As the leaving water temperature approaches its set temperature, units shut down in
succession, starting with the unit with the lowest address (the master unit). Once the set temperature has been
reached, the unit with the highest address shuts down.
Figure 3-7.1 shows an example of duty cycling in a system with 16 outdoor units.
Figure 3-7.1: Duty cycling in a system with 16 outdoor units
1
Notes:
1. The address settings on the outdoor unit main PCBs for master unit and slave unit do not change.
7.2 Defrosting Operation
In order to recover heating capacity, the defrosting operation is conducted when the outdoor unit air side heat exchanger
is performing as a condenser. The defrosting operation is controlled according to outdoor ambient temperature, air side
heat exchanger refrigerant outlet temperature and the compressor running time.
The defrosting operation ceases when any one of the following three conditions occurs:
 Defrosting operation duration reaches 10 minutes.
 The air side heat exchanger refrigerant outlet temperature reaches the target temperature.
 The water outlet temperature is at or below 5°C .
Startup control
Normal operation
After defrosting operation or on
restart following compressor stop
after set temperature s reached
Normal operation
Outdoor unit
duty cycling
Priority
1
Priority
2
……
Priority
16
Master
Slave 1
Slave 15
Outdoor unit
duty cycling
Priority
16
Priority
15
Priority
1
Master
Slave 1
Slave 15
……

Midea MC-SU60-RN1L Specifications

General

Brand	Midea
Model	MC-SU60-RN1L
Category	Chiller
Language	English