Mitsubishi Electric PURY-P72 Service Handbook page 127

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[VI
Refrigerant Circuit]
Part Symbols
Notes Usage
Specifications Check method
name
(functions)
Thermis- TH3 Controls defrosting during heating Degrees Celsius Resistance
tor (Pipe operation
Ro = 15kQ
check
tem perature)
R1lI80= 3460
1 1
TH7 1) Detects outdoor air tempera-
RI = 15expl3460
(273+i -
m}l
(Outdoor tem-
ture
perature)
2) Controls fan operation
0°C[32°F] :15kohm
TH5 Fan operated on the 63LS and
10°C[50°F] :9.7kohm
TH5 values.
20°C[68°F] :6.4kohm
25°C[77°F] :5.3kohm
TH6 Controls defrosting during heating
30°C[86°F] :4.3kohm
operation
40°C[1 04OF] :3.1 kohm
THHS Controls inverter cooling fan Degrees Celsius
Inverter based on THHS temperature
heat sink tem-
Roo = 17kll
R251120 = 4016
perature
RI= 17expl4016
(27~+1- 3~3)1
THBOX
Control box in-
ternal tempera-
0°C[32°F] :161 kohm
ture detection
10° C[50° F) :97kohm
20°C[68°F] :60kohm
25°C[77°F] :48kohm
30°C[86°F] :39kohm
40°C[104°F] :25kohm
Sole-
SV1a 1) High/low pressure bypass at
AC208-230V Continuity
noid Discharge-suc-
start-up and stopping, and
Open while being poweredl check with a
valve tion
capacity control during low-
closed while not being pow- tester
bypass
load operation
ered
SV2
2) High-pressure-rise preven-
tion
SV4a - SV4d Controls outdoor unit heat ex-
Heat changer capacity
exchanger
capacity control
SV5b Prevents high-pressure-rise AC208 -230V
Heat
Controls defrost cycle
Closed while being poweredl
exchanger open while not being powered
capacity control
SV5c Allows the refrigerant to pass AC208 -230V
through the bypass pipe to pre- Open while being poweredl
vent an accumulation of liquid re- closed while not being pow-
frigerant ered
SV9 High-pressure-rise prevention
AC208 -230V
Open while being poweredl
closed while not being pow-
ered
Heater CH11 Heats the refrigerant in the com- Cord heater
Resistance
pressor
P72 model cheCk
1035 ohm 51W
P96, P120 models
928 ohm 57W
4-way 21S4a Changeover between heating and AC208-230V Continuity
valve cooling Dead: cooling cycle check with a
Live: heating cycle
tester
HWEOB03A
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GB