Mitsubishi PUHY-EP250 Service Handbook page 68

[3-3 Functions of the Major Components of Outdoor Unit ]
Part Symbols
name (functions)
Sole- SV1a
noid Discharge-
valve suction
bypass
SV5b
Heat
exchanger
capacity con-
trol
SV5c EP300 -
EP450
models
only
SV9
SV2
Linear LEV1
expan- (SC control)
sion
valve
LEV2
(Refrigerant
flow adjust-
ment)
4-way 21S4a
valve
21S4b
21S4c EP300-
EP450
models
only
Fan FAN motor FAN mo-
motor 1,2 tor 2 is
only on
the
EP350 -
EP450
models.
HWE12050
Notes Usage
1) High/low pressure bypass at
start-up and stopping, and
capacity control during low-
load operation
2) High-pressure-rise preven-
tion
Controls outdoor unit heat ex-
changer capacity
High-pressure-rise prevention
High-Low pressure bypass during
defrost
Adjusts the amount of bypass flow
from the liquid pipe on the outdoor
unit during cooling
Adjusts refrigerant flow during
heating
Changeover between heating and
cooling
1) Changeover between heating
and cooling
2) Controls outdoor unit heat ex-
changer capacity
Regulates the heat exchanger ca-
pacity by adjusting the operating
frequency and operating the pro-
peller fan based on the operating
pressure.
Specifications
AC220-240V
Open while being powered/
closed while not being pow-
ered
AC220-240V
Closed while being powered/
open while not being powered
Open while being powered/
closed while not being pow-
ered
Open while being powered/
closed while not being pow-
ered
DC12V
Opening of a valve driven by a
stepping motor 0-480 pulses
(direct driven type)
DC12V
Opening of a valve driven by a
stepping motor 2100 pulses
(Max. 3000 pulses)
AC220-240V
Dead: cooling cycle
Live: heating cycle
AC220-240V
Dead: cooling cycle
Outdoor unit heat exchanger
capacity at 100%
Live: heating cycle
Outdoor unit heat exchanger
capacity at 50%
or heating cycle
AC380-400V, 920W
- 59 -
Check method
Continuity check
with a tester
Same as indoor
LEV
The resistance val-
ue differs from that
of the indoor LEV.
Refer to the follow-
ing page(s). [8-8
Troubleshooting
LEV Prob-
lems](page 228)
Refer to the section
"Continuity Test
with a Tester".
Continuity between
white and orange.
Continuity between
yellow, brown, and
blue.
White
M
Orange
Yellow Brown Blue
Continuity check
with a tester
GB