Kaisai 06RY1, Service Manual

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M thermal Mono
24 202008
Midea
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ual
5.8 Module Temperature Protection Control
This control protects the module from abnormally high temperatures
.
Figure 3-5.3: Module Temperature Protection Control
When the module temperature rises at or above Tf2 the system displays C7 protection and the unit stops running. When
the module temperature drops at or below Tf0-1, the compressor enters re-start control.
6kW 8-10kW
Tf2 75 81
Tf0 69 75
Module temperature ≥ Tf2
Module temperature ≤ Tf0-1°C
Normal operation
Module Temperature Protection, error code C7 is displayed
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12-16kW 3ph
84
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M thermal Mono
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Part
3
- Con
trol
6 Special Control
6.1 Oil Return Operation
In order to prevent the compressor from running out of oil, the oil return operation is conducted to recover oil that has
flowed out of the compressor and into the refrigerant piping. When the oil return operation is being conducted, the
outdoor unit refrigerant system main PCB displays code d0.
Timing of oil return operation:

When the compressor cumulative operating time with running rotation speed less than 42rps reaches 6 hours.
The oil return operation ceases when any one of the following three conditions occurs:

Oil return operation duration reaches 5 minutes.

Compressor stops.

Mode change command is received.
Tables 3-6.1 show component control during oil return operation in cooling mode.
Table 3-6.1: Outdoor unit component control during oil return operation in cooling mode
Component
Wiring diagram
label
6kW
8/10/12/
14/16kW
Control functions and states
Inverter compressor COMP
● ●
Runs at oil return operation rotation speed
DC fan motor FAN
● ●
Controlled according to outdoor heat exchanger pipe
temperature
Electronic expansion valve EXV
● ●
304 (steps)
Four-way valve ST
● ●
Off
Tables 3-6.2 show component control during oil return operation in heating and DHW modes.
Table 3-6.2: Outdoor unit component control during oil return operation in heating and DHW modes
Component
Wiring diagram
label
6kW
8/10/12/
14/16kW
Control functions and states
Inverter compressor COMP
● ●
Runs at oil return operation rotation speed
DC fan motor FAN
● ●
Controlled according to outdoor heat exchanger pipe
temperature
Electronic expansion valve EXV
● ●
304 (steps)
Four-way valve ST
● ●
On
6.2 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.
Table 3-6.3: Component control during defrosting operation
Component
Wiring diagram
label
6kW
8/10/12/
14/16kW
Control functions and states
Inverter compressor COMP
● ●
Runs at defrosting operation rotation speed
DC fan motor FAN
● ●
Off
Electronic expansion valve EXV
● ●
Fully open
Four-way valve ST
● ●
Off
6.3 Fast DHW Operation
Fast DHW operation is used to quickly meet a requirement for domestic hot water when DHW priority has been set on the
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