Midea MSY-09HRDN1-QC2, Service Manual

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8.5 Cooling Mode
8.5.1 The operation frequency of compressor after starting submits to following rule.
When the machine is running and Δ T(=room temp. – setting temp.) changes, the
frequency of compressor will rise or descend a grade (7 minutes after starting).
After starting, if Δ T stays in a zone for 3 minutes, the frequency will change as follow:
Zone A : Current frequency rise a grade till the maximum grade F8.
Zone B: Keep the current frequency of compressor.
Zone C: Descend the current frequency of compressor until F1.
Zone D: Compressor stops after running as the minimum frequency F1 for 60 minutes or Δ T is
less than -2
℃
.
8.5.2 Indoor heat exchanger anti-freezing function.
If T2 is lower than 0
℃
, the compressor stops and resumes when T2>5
℃
.
8.5.3 Outdoor unit current control in cooling mode.
8.5.4 Rating capacity test function
1) Set the indoor unit with remote controller as: high fan, 17
℃
in cooling mode, then press “ TURBO ”
button on controller 6 times or more within 10 seconds (make sure indoor unit receives these signals),
the machine will turn into rating capacity test mode, the buzzer will make a
“ di ” sound for 2 seconds
continuously. Also, indoor fan will change to rating speed, the frequency of compressor will be fixed
as rating value. Any condition of above is not satisfied, the machine cannot be turned into rating
capacity test mode.
2) The machine will quit from the rating capacity test mode if running for 5 hours or changing fan
speed or setting temperature.
8.5.5 Turbo function(press the
“ TURBO ” button on remote controller)
Elevate current frequency to a higher grade.
D
-1.0
B
1.0
-0.5
0.5
1.5
C
I3COOL
I2COOL
I1COOL
comp. pause
freq. descends if curr. rises;
freq. remains if curr. descends
running normally
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