Trane 4TXK6512G1000AA, Service Manual

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4. The limitation of the EEV opening
State of the unit Requirement of the opening Lower limit Upper limit
Shut down
Standard opening of the model, according to the
opening of last time
/ /
Standby
(temperature sensor off)
Standard opening of the model, according to the
mode before the temperature sensor is off
/ /
Cooling startup process Execute the standard cooling opening of the model Standard opening 400
Heating startup process Execute the standard heating opening of the model 150 400
Cooling, dehumidification Adjust automatically 70 470
Heating Adjust automatically 70 470
Defrosting Fixed opening 200 400
Oil return Fixed opening 150 400
Refrigerant discharge Fixed opening 150 400
9.4.6 Control of shutdown
1. Initiative shutdown mode (shutdown normally without protection)
When the air conditioner is in cooling or heating mode, the compressor get the shutdown signal, the current
frequency of the compressor is more than 55HZ (EE) , the compressor will decrease to 48HZ at the speed of
2HZ/s and shut down directly.
If the current frequency of the compressor is lower than 55HZ, it will shut down directly after it receives the
signal. Avoid that the sudden shutdown will cause too strong stress when in high working frequency.
After the compressor stops, the fan motor will execute the left heat blowing and then stops.
Shutdown because of the anti-freeze protection, the compressor will stop as initiative shut down mode/
2. Passive shut down mode (Error protection shut down)
When the system come to the pressure protection, over-current protection, high module temperature protection,
high condensation temperature protection and the unit shut down, no matter the frequency of the compressor
come to 55HZ, the unit will shut down directly.
9.4.7 Defrosting control in heating mode
In heating mode, condenser heat exchanger defrosting condition is detected by outdoor coil temperature
sensor, and defrosting is controlled by outdoor ambient temperature and coil temperature.
1. Defrosting starting condition:
1) After compressor running in heating for continuous 10 minutes (E) and for accumulated 50 minutes (E) , by
testing Te (defrosting temp sensor) or TC (testing of outdoor exchanger frosting condition) and outdoor ambient
temp sensor TA, when it meeting the following condition for continuous 5 minutes, the unit will enter defrosting
operation. In case of no defrosting operation caused by imbalanced refrigerant flow (caused by refrigerant lack or
other reason) , the unit will enter defrosting when any one of the two conditions are meet.
Entering condition:
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