Heating High Pressure Control - Mitsubishi Heavy Industries FDT40ZSXW1VH Service Manual

(c) Reset conditions
When either of the following condition is satisfied.
1) The outdoor air temperature (TH2) is D°C or higher.
2) The compressor speed is 0 rps.

(5 ) Heating high pressure control

(5) Heating high pressure control
(a) Purpose
(a) Starting condition
When the indoor heart exchanger temperature (Thi-R) has risen to a specified temperature while the compressor is turned on.
(b) Detector
(b) Compressor speed is controlled according to the zones of indoor heat exchanger temperature as shown by the following
table.
(c) Detail of operation
(Example)
Protection control speed (NP)
Compressor
Sampling time (s)
speed
NP
NP<50
50≦NP<115
115≦NP<120
120≦NP
(6) Heating overload protective control
(a) Operating condition
When the indoor heat exchanger temperature is in the range of A-B °C, if the compressor speed is been maintained and the operation has continued for more
than 20 seconds at the same speed, it returns to the normal heating operation.
fan
Temperature list
Models SRK20, 25, 35
(b) Detail of operation
(i)
RPSmin < 50
50 < = RPSmin < 91
(ii)
91 < = RPSmin < 97
fuzzy calulation, the speed is kept to 30(40) rps. However, when the thermostat OFF, the speed is reduced to
97 < = RPSmin < 100
100 < = RPSmin < 115
0 rps.
115 < = RPSmin
(iii)
40 rps.
(iv) The outdoor fan speed is stepped down by 3 speed step.(Low limit 2nd speed)
(c)
Reset condition
Upper 90 rps
Lower 30 rps
OFF
11
Outdoor air temperature(ºC)
THi-R
Thi-R<P1
Normal
After lapse of 20 sec. or over
Normal
After lapse of 20 sec. or over
After lapse of 20 sec. or over
P1 P2
Thi-R
45 52
45 52
45-43 52-50
A
43 50
Indoor heat exchanger temperature(°C)
13
H
speed
A
48 53
48.5 56
48.5 56 - 52.5
48.5 52.5 - 50.8
48.5 - 40.1 50.8 - 42
40.1 42
H
Upper 75 rps
Lower 40 rps
13 16 17
P1≦Thi-R<P2 P2≦Thi-R<P3
Retention NP-4rps
4rps 8rps
(3) (1)
10 10
4rps
(1)
(3)
Unit:°C
lower limit
(3)
speed 35 rps
P3
54.5
57
57-55
B C
55
B - C
C - D
fan
90(75) rps
B C
55
58
30(40) rps
58
58 - 56.2
56.2 - 47.3
47.3
11
29
- -
'19 • PAC-SM-302
P3≦Thi-R
NP-8rps
(2)
10
8rps
(2)
0rps
D
10
10
speed is
D
58
61
than that after
61
61
61
61