Electra AWAU-VBZE218-H11, Service Manual, Page: 35 / 58

Service Manual – V BZE DCI 1-A.1 GB
CONTROL SYSTEM
12–9
12.7.4 Compressor over Heating Protection
The Discharging temperature is used as the compressor’s internal temperature. If the discharge
temperature rises above a certain level, the operating frequency upper limit is set to keep this
temperature from going up further.
Compressor frequency will be reduced when CTT reaches above 97C
Compressor will stop when CTT reaches 110C
If the unit stops as such protection for 6 times (the counter will be cleared after the compressor has
run for 7min) , it can not resume running automatically and display malfunction, it can resume by
remote control ON/OFF reset.
12.7.5 Compressor over Current Protection
Detect an input current by the CT during the compressor is running, and set the frequency upper limit
from such input current. In case of heat pump model, this control is the upper limit control function of
the frequency which takes priority of the lower limit of four way valve activating compensation.
Detail
For model 14: Compressor will stop when AC current >= 16.0A for continuously 2.5s
For model 18/30: Compressor will stop when AC current >= 20.0A for continuously 2.5s
If the unit stops as such protection for 6 times (the counter will be cleared after the compressor has
run for 7min), it can not resume running automatically and display malfunction, it can resume by
remote control ON/OFF reset.
12.7.6 Outdoor Coil Deicing Protection
This protection is for Heat Pump Only
This protection is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor heat
exchanger temperature must be more than its setting values when finishing the deicing protection.
In the deicing protection, IFAN is forced OFF.
12.7.6.1 Deicing Starting Conditions
The starting conditions must be made with the outdoor air temperature (OAT) and outdoor coil
temperature (OCT). Under the conditions that the system is in heating operation, after the time
for defrosting is judged to be satisfied, if the temperature for deicing is satisfied after detections
for continuous 1 minute, the deicing operation will start.
Deicing interval time is changed as a function of deicing time. If deicing time is shorter than
former deicing time, the deicing interval time will be increased. If deicing time is longer than
former deicing time, the deicing interval time will be decreased.