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Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
28
Special Control
Table 29 —Startup Control
SEQUENCE:
Sequence A: T5 ≥ 59°F and T4 ≥ 23°F, or T4 ≥ 37.4°F.
Sequence B: 23°F ≤ T4 < 37.4°F.
Sequence C: 5°F ≤ T4 < 23°F.
Take sequence A as an example, and assume that the target frequency is 50 Hz.
The compressor runs 33 Hz and 42 Hz for 60 seconds respectively, and goes to 50 Hz afterward.
If the target frequency is higher than 66 Hz, the ODU needs to operate at 33, 42, 56, 66 Hz respectively for one minute, or it directly
goes to the target frequency like the example above.
A210269
Fig. 35 —Sequence for Startup Control
SV5 will open if heating frequency ≥ 50 Hz with startup manner A or B.
Component
Cooling Operation
Heating Operation
Remark
Compressor
Capacity demand control
Capacity demand control
Sequence
*1
A to C
Outdoor unit fan
W7 for twenty seconds, then control based
on frequency, T4, T5, and Tc
Maximum speed referred to T4 and
frequency
4-Way Valve (ST1)
OFF
ON
EEV
300 pls for three minutes after compressor
starts, then normal control
300 pls for three minutes when T4 ≥ 32°F
300 pls for 6minutes when T4 < 32°F
Then normal control
Fast oil return (SV4)
ON
ON
Continuous time based on T4
Hot gas bypass valve (SV5)
OFF
Bypass control
*2
Spraying liquid valve (SV6)
OFF
OFF
Ending conditions
According to target frequency and startup stage