Lev Control - Mitsubishi Electric MXZ-18NV Service Manual

No. Item
1

LEV control

32
Linear expansion valve (LEV) is controlled by "Thermostat ON" commands given from each unit.
Indoor unit status
All indoor units OFF
Non-opening indoor unit
Thermostat OFF in
COOL or DRY mode
Thermostat ON in COOL mode
Thermostat ON in DRY mode
Thermostat OFF in HEAT mode
Thermostat ON in HEAT mode
For the differential start-up, the LEV is controlled at 52 pulse for the first 15 minutes after
compressor stop.
Standard LEV opening
There are 10 levels specified for standard LEV opening depending on the compressor operational
frequency. Based on these standard valves, the LEV opening is modified according to the suction
superheat, discharge temperature, and gas pipe temperature.
<LEV opening>
Level 10
Level 09
Level 08
Level 07
Level 06
Level 05
Level 04
Level 03
Level 02
Level 01
30
<Standard LEV opening by capacity code>
MXZ-18NV-E1
Capacity class
Level 01
Level 02
Level 03
Level 04
Level 05
Level 06
Level 07
Level 08
Level 09
Level 10
Details
MXZ-18NV
Before shutdown 350 pulse
COOL : 5 pulse
HEAT : 49 pulse
Outdoor unit ON (Indoor unit ON) : 5 pulse
Outdoor unit OFF (Indoor unit OFF or
Thermostat OFF) : Before shutdown
Refer to the standard LEV opening as shown below.
From the initial valve, the LEV opening is controlled according
to suction superheat and the discharge temperature.
Refer to the standard LEV opening as shown below.
Outdoor unit ON (Indoor unit ON) : 49 pulse
Outdoor unit OFF (Indoor unit OFF or
Thermostat OFF) : Before shutdown
Refer to the standard LEV opening as shown below.
From the initial valve, the LEV opening is controlled according
to the suction superheat and the discharge temperature.
40 50 60 70 80 90
MXZ-18NV-E2
09 07,09
100/70 255/70 255/90
100/70 255/70 255/90
255/70 255/90
100/70
100/70 255/70 255/90
100/70 255/70 255/90
110/80 255/80 255/100
120/90 255/90 255/110
130/100 255/100 255/120
140/110 255/110 255/130
150/120 255/120 255/140
LEV opening
MXZ-32NV
52 500 pulse
COOL : 5 pulse
HEAT : 59 pulse
Outdoor unit ON (Indoor unit ON) : 5 pulse
Outdoor unit OFF (Indoor unit OFF
or Thermostat OFF) :
Outdoor unit ON (Indoor unit ON) : 5 pulse
Outdoor unit OFF (Indoor unit OFF
or Thermostat OFF) :
Hysteresis width
=5Hz
100 110 120 < COMP Hz >
MXZ-32NV-E1,E2
12 07,09 12,13
100/70 130/90
100/70 130/90
100/90 130/110
100/110 130/130
100/130 130/150
110/150 140/170
120/170 150/190
130/190 160/210
140/210 170/230
150/230 180/250
52 500 pulse
52 500 pulse
18
145/100
145/100
145/120
145/140
145/160
155/180
165/200
175/220
185/240
195/260