Mitsubishi Electric MXZ-18TV, Service Manual

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16
(1) LEV opening correction by suction super heat (COOL, DRY)
(Suction super heat) = (Minimum gas pipe temperature) - (Evaporation temperature)
When COOL and DRY , correct the LEV openings corrected from the table below
(2) Separate correction (COOL,DRY)
(When number of operation unit is 2 units)
(a) Correction by the separate super heat
Correct the LEV separately by temperature difference between each gas pipe temperature thermistor and evaporator
temperature thermistor.
1
Calculate each super heat of the unit from the expression below;
(Super heat) = (Gas pipe temperature thermistor) - (Evaporation temperature thermistor)
2
Select a minimum super heat from among them.
3
Correct an each LEV is corrected opening is corrected by difference between each super heat and minimum super
heat.
Suction superheat (S.H.)
LEV opening
correction (pulse)
more than 12
10 to12
8 to 10
6 to 8
6 or less
6
4
3
2
0
Difference of
superheat LEV opening
correction (pulse)
more than 9
6 to9
3to 6
6 or less
8
6
2
0
1
Suction super heat
(MIN gas pipe temperature thermistor - Evaporation temperature thermistor)
2
Each correction
w
1
• (Each gas pipe temperature thermistor - Evaporation temperature thermistor)
• (Main pipe temperature thermistor - sub pipe temperature thermistor)
w
1 Perform this, when number of operation units is 2units or more
w
2 When the correction opening of suction super heat is 0, correct the LEV opening by dischaege temperature.
3
Discharge temperature
COOL DRY HEAT
• •
-
•
w
2
•
w
2
•
<Correction>
2 Code3 Code2
Standard opening
Difference in
capacity
Difference in
operation number
1 2 3 4 5 6 7 8
COOL
HEAT
150
120
160
130
170
140
180
150
Capacity code
Indoor unit
1
07
2
09
3
12
4
18
190
160
190
170
200
180
200
180
25
20
50
40
-60
-60
OB280-1.qxp 01.4.4 2:40 PM Page 16