Protective Control Function - Mitsubishi Heavy Industries SRK15ZTL-W Service Manual

(22) Protective control function

(a) Dew prevention control (During cooling)
Prevents dewing on the indoor unit
(i) Operating conditions
When the following conditions have been satisfied for more than 30 minutes after starting operation
1) Compressor's speed is 26 (model SRK50:28) rps or higher.
2) Detected value of humidity is 68% or higher.
(ii) Contents of operation
1) Air capacity control
Item
ULO
LO
AUTO, MED
HI
Note Ranges A and B are as shown below.
Range A
2) When this control has continued for more than 30 minutes continuously,the following wind direction control is performed.
a) When the vertical wind direction is set at other than the vertical swing,the flaps change to the horizontal position.
b) When the horizontal wind direction is set at other than the horizontal swing,the louver changes to the vertical position.
(iii) Reset condition
Humidity is less than 63%.
(b) Frost prevention control
(i) Operating conditions
1)
2)
(ii) Detail of anti-frost operation
Indoor heat exchanger
Item
Lower limit of compressor command speed
Indoor fan
Outdoor fan
4-way valve
(iii) Reset conditions
1)
2)
Model
RangeA: 34rps
Upper limit of
compressor's speed
RangeB: 28rps
Indoor fan
RangeA: 42rps
Upper limit of
compressor's speed
RangeB: 30rps
Indoor fan
RangeA: 52rps
Upper limit of
compressor's speed
RangeB: 52rps
Indoor fan
RangeA: 66rps
Upper limit of
compressor's speed
RangeB: 60rps
Indoor fan
Range B
68 73
Humidity(%)
temperature 5°C or lower
(model SRK50 : 23 rps)
Depends on compressor speed
SRK15 SRK20
RangeA: 36rps
RangeB: 28rps
RangeA: 45rps
RangeB: 30rps
5th speed
RangeA: 56rps
RangeB: 52rps
Adaptable to compressor speed
RangeA: 70rps
RangeB: 60rps
7th speed
2.5°C or lower
Keep the fan speed before
frost prevention control
2.5–5
5–8
14
- -
'22 • SRK-SM-349
SRK25, 35
RangeA: 46rps RangeA: 40rps
RangeB: 46rps RangeB: 28rps
4th speed
RangeA: 46rps RangeA: 66rps
RangeB: 46rps RangeB: 28rps
Adaptable to compressor speed
RangeA: 55rps RangeA: 82rps
RangeB: 55rps RangeB: 40rps
RangeA: 60rps RangeA: 100rps
RangeB: 60rps RangeB: 50rps
Adaptable to compressor speed
'09•SRK-DB-087D
compressor
speed
Lower
limit
speed
0 rps
2.5
Indoor heat exchanger
temperature (°C)
SRK50
5 8