Mitsubishi Electric MXZ-18TV Service Manual page 17

(3) LEV opening correction by discharge temperature
When LEV correction output is 0 pulse by the suction super heat at cool or dry operation, or dry operating, correct LEV is cor-
rected according to the following table.
The target discharge temperature is determined according to frequency zone and number of operation unit of the
compressor.
Operation frequency
of compressor
Minimum ~ 20
21 ~ 33
34 ~ 46
47 ~ 59
60 ~ 72
73 ~ 85
86 ~ 98
97 ~ 111
111 ~ Maximum
Correct the LEV opening according to difference between the target discharge temperature and discharge temperature.
more than Target discharge temperature+11
Target discharge temperature+11 to Target discharge temperature+8
Target discharge temperature+8 to Target discharge temperature+5
Target discharge temperature+5 to Target discharge temperature+2
Target discharge temperature+2 to Target discharge temperature-2
Target discharge temperature-2
Target discharge temperature-5
Target discharge temperature-8
Target discharge temperature-11 or less
11-2.Operational frequency range
Number of
capacity
operating
cord
Min.
unit
1
1 2 30
3
2
3
4
30
2 5
6
7
11-3.Heat defrosting control
(1) Conditions to enter defrosting mode
1. When temperature of defrosting thermistor is -3; or less.
2.When specified non-defrosting time, is counted in the control p.c.board is satisfied.
(Total time of compressor operating)
Going to defrosting mode at both condition of 1 and 2.
(2) Defrosting operation
1. Compressor stops for 50 seconds, Indoor fan is off, Defrosting lamp lights
2.4-way valve reverses flow, Compressor operates by the frequency in heat defrosting control.
3. After compressor stops for 35 seconds, 4-way valve reverses flow, then defrosting finishes.
(3) Conditions to finish defrosting mode
1. When the defrosting thermistor temperature is 8; or more.
2. When it has spent 10 minutes for defrosting.
Defrosting finishes at condition of 1 or 2.
COOL, DRY
Number of operating unit.
Single
40
40
45
45
50
55
65
70
75
Discharge temperature (;)
to Target discharge temperature-5
to Target discharge temperature-8
to Target discharge temperature-11
COOL DRY
Max. Rated Min.
70 55 30
80 61 41 30
100 85 53
120 108 72 30
Number of operating unit.
Double Single
40 40
40 45
45 50
45 55
50 60
55 65
65 70
70 75
75 75
HEAT
Max. Defrost Rated
100 100 80
100 100 85
120 100 94
120 100 120
Note: When the fan speed of indoor unit is total
Lo notch, restrict the maximum frequency is
rated frequency.
17
HEAT
Double
40
45
50
55
60
65
70
73
73
LEV opening
correction (pulse)
COOL HEAT
10 8
4 2
2 1
1 1
0 0
-1 -1
-2 -1
-5 -2
-8 -6