Daikin FTKB12AXVJU - Defrost Cycle

Algorithm & Control
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2.18.3 Limit Rotation
Determine from
• Upper limit rotation
A minimum value was determined among the upper limits rotation, i.e. protection controls.
• Lower limit rotation
A maximum value was determined among the lower limits rotation, i.e. protection controls.
Generally, compressor rotation is controlled within 5 zones: stop, drop, keep, up and reset subjected to a
particular operating temperature/current/pressure.
Zone Control
Stop
Compressor is stopped when a certain limit reaches the stop zone for abnormality
correction.
Drop Frequency will be dropped with a timer setting.
Keep Frequency is maintained at lower/upper limit.
Up Frequency will be increased with a timer setting.
Reset Frequency lower/upper limit is canceled and returned to command rotation.
2.19 Defrost Cycle
Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor heat exchanger
temperaturemustbemorethanacertainvaluetonishdefrosting.
During defrost All models
Compressor ON
4-way valve OFF
EXV in operation room Fixed opening
Outdoor fan OFF
Indoor fan OFF
Conditions for starting Defrost
•Thestartingconditionsaredeterminedwiththeoutdoortemperatureandtheoutdoorheatexchanger
temperature
•Thesystemisinheatingcondition
•Compressorminimumruntime–6minutesOR
•MorethanAminutes(dependingonthedurationofthepreviousdefrostcontrol)ofaccumulatedtime
have passed since the start of the operation, or ending the previous defrosting
Condition for terminating defrost
The judgment is made with the outdoor heat exchanger temperature (B°C)