Daikin RMXS-L Series, Руководство по обслуживанию

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SiUS181305E Branch Provider (BP) Unit Control
Function 60
6.3 SH Control in Cooling Operation
Outline This function ensures appropriate refrigerant distribution when many indoor units are operating in
cooling operation.
Detail The heat exchanger temperatures and gas pipe temperatures of operating indoor units are
detected by the gas pipe thermistors, and the flow rates of the electronic expansion valve are
corrected so as to adjust the difference between the heat exchanger temperature and gas pipe
temperature of each indoor unit (hereafter referred to as SH) close to the target values.
When SH is higher than target value

Opens the valve of that indoor unit
When SH is lower than target value

Closes the valve of that indoor unit
When the liquid pipe temperature is lower than the heat exchanger temperature, the electronic
expansion valve is opened more than normal opening.
(Protection function to prevent rotor dew condensation)
The gas pipe temperature and indoor heat exchanger temperature are detected with a sampling
time of 40 seconds for the cooling SH control.
In order to prevent dew condensation in the connection pipe, the gas pipe lower-limit temperature is
set as follows.
(R19087)
Gas pipe lower limit temperature (˚C) = × outdoor temperature (˚C) – 17
240
256
(Gas pipe lower limit temperature (˚F) = × outdoor temperature (˚F) – 28.6)
Gas pipe lower limit temperature
≤
8˚C (46.4˚F)
240
256
(˚C) (˚F)
–25
–20
–15
–10
–5
0
5
10
8
–13
–4
5
14
23
32
41
50
46.4
–5 0 5 10 15 20 25 30 35 40 45
Outdoor temperature
Gas pipe lower limit temperature
(˚C)
23 32 41 50 59 68 77 86 95 104 113 (˚F)