Heating High Pressure Control - Mitsubishi Heavy Industries SRK20ZJX-S Service Manual

(5) Heating high pressure control

(a) Indoor unit side
1) Start condition: When the indoor heat exchanger temperature (Th2) has become higher than the start temperature for
2) Contents of control: Compressor stop
Indoor
air temp.(Th1)
Th1 < = 24°C
24°C < Th1 < = 27°C
27°C < Th1
3) Release condition: When the indoor heat exchanger temperature (Th2) has become lower than the release tempera-
(b) Outdoor unit side
1) Start condition: When the indoor heat exchanger temperature (Th2) has risen to a specified temperature while the
2) Compressor command speed is controlled according to the zones of indoor heat exchanger tem-
perature as shown by the following table.
Protection control speed (NP)
Sampling time (s)
• Model SCM40~50
Th2
NP
<
10 = NP < 115
<
115 NP < 120
=
<
120 = NP
(6) Heating overload protective control
(a) Indoor unit side
1) Operating conditions :
2) Detail of operation :
3) Reset conditions :
(b) Outdoor unit side
1) Operating conditions :
2) Detail of operation
B or D.
3) Reset conditions:
Upper A
Lower B
OFF
11(8) 13(10)
Outdoor air temperature(
Note(1) Value in ( ) are for the model SCM40, 45.
1 minute continuously.
Item
Release temperature
48.5°C
47.5°C
46.5°C
ture.
compressor is turned on.
<
Th2 < P1 P1 Th2 < P2
=
Normal Retention
Normal 20
P1 P2
45 52 57.5
45 ~ 43 52 ~ 50 57.5 ~ 55
43 50
Upper C
Lower D
-
16 17
)
º
Start temperature
62°C
61°C
60°C
< <
P2 Th2 < P3 P3 Th2
= =
NP 4rps NP 8rps
20 20
• Model SCM60~80
Unit: °C
Th2
P3
NP
<
10 = NP < 90
<
90 NP < 100
=
<
55 100 = NP < 110
<
110 NP < 120
=
<
120 = NP
h
h
h 10 or 17
A or C
B or D
B or D when the thermo becomes OFF, the speed is
h 8
(model 60 ~ 80:11 ).
Item
A
Model
SCM40, 45 90
SCM50
90
35
-
SCM60, 71, 80 90
'10 • SCM-SM-094
Unit: °C
P1 P2 P3
45 52 57
45 ~ 44.5 52 ~ 49.5 57 ~ 54
'09•SRK-DB-087D
44.5 ~ 44 49.5 ~ 47.5 54 ~ 51
44 ~ 43 47.5 ~ 45 51 ~ 48
45
43 48
(SRF, SRR:9th, FDTC:4th)
(model 60 ~ 80:13
or 17
Unit: rps
B C D
35 75 40
35 75 40
30 75 40
)