Service manual

ESIE03–01 Overview of the cooling mode functions
Part 2 – Functional Description 2–33
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2.4 Outdoor Fan Starting Control in Cooling or Dry Keep Mode
Applicable units P R(Y)P71-125L
Purpose The purpose is to avoid that the discharge pressure would start to rise, and stop the unit.
Method:
R(Y)P71-125L
When the compressor starts, the fan keeps running for 3 min at starting fan speed. The starting fan
speed depends on the ambient temperature. The different fan speeds for the according outdoor air
temperatures are shown in the table below.
(*) When cutting jumper J3, the 20 second timer is changed to 5 seconds
Fan speed for
Ta < 3°C:
R(Y)P71-125L
This fan starting control is made to be able to build up the compression ratio as soon as possible
because this has two advantages:
P It is better for the compressor to increase the compression ratio because the lubrication must be
done by the pressure difference between low and high pressure.
P The pressure difference is necessary for the h/p models to keep the 4-way valve in its correct
position.
Operating mode Outdoor air temp. Ta Starting fan speed
See further in this
section...
Cooling mode,
dry keep mode
area 1: Ta < 3°C Fan speed for
Ta < 3°C:
R(Y)P71-125L
area 2: 3°C ≤ Ta < 10°C L speed Different fan
speeds
area 3: 10°C ≤ Ta < 23°C L speed
area 4: Ta ≥ 23°C HH speed
Area 2~4:
Area 1:
Outdoor fan:
Compressor:
Outdoor fan:
Compressor:
ON
OFF
ON
OFF
ON
OFF
ON
OFF
20 sec
10 sec