Table of Contents
Function
1.5.3
Pump Down Start (CU-8·10 only)
If the compressor stops running with refrigerant still remaining in the accumulator, in order to prevent wet
operation at the next compressor starting, it will perform pump down start with a completely dry
accumulator, then it will operate normally.
Pump down start should be performed if the unit is in any of the conditions given below when pressure
equalizing control has been completed before start.
If R3-1T is less than 95°C and the unit is in any of the following conditions.
‹ Within 10 minutes of the compressor starting
‹ Defrosting or during oil return
‹ Within 20 minutes of completion of defrost or oil return
‹ Outdoor air temperature (R1T) < 0ºC
‹ Oil temperature (R5T) < Te + 10ºC
„ MX1R Series
Operation During
Pump Down Start
Compressor
Outdoor unit EV
Outdoor unit fan
Y2S
Y3S, Y4S
*
„ ME1R Series
Compressor
Outdoor unit EV
Outdoor unit fan
Y2S
Y3S
‹ Y2S: Hot gas bypass solenoid valve
‹ Y3S: Injection solenoid valve
1.5.4
Heating Lay-Up Start
If the compressor hasn't run for a long time and the refrigerant isn't circulated, foaming could cause a lack
of oil when the compressor is started at the next time. It should therefore perform heating lay-up start to
keep the low pressure from dropping too low in the following cases.
‹ First starting after being power ON.
‹ Starting after the compressor has been stopped or thermostat OFF for more than continuous 24 hours.
Operation During
Make the compressor's upper limit frequency 62Hz (62Hz+OFF) for 10 minutes 20 seconds after the
Heating Lay-Up
compressor starts.
∗ If low pressure becomes < 1.5 kg/cm² (0.147MPa), operating frequency becomes 54Hz.
Start
244
Te : Low pressure equivalent saturated temperature
1 min.
42Hz+OFF
0 pulses
H tap
(H+ON)
ON
ON
When heating, low pressure < 1.5 kg/cm
2
(0.167MPa) [30 sec. continuous] → release
Low pressure > 1.7 kg/cm
← 11 min. 30 sec. →
1 min.
42Hz+OFF
0 pulses
H tap (H+ON)
ON
ON
If low pressure becomes > 1.7 kg/cm² (0.167MPa), the heating lay-up operation is released.
11 min. 30 sec.
5 min.
30 sec.
62Hz+OFF
32Hz+OFF
0 pulses
H tap
(H+ON)
ON
ON
ON/OFF
(Td protection control)
(Td protection control)
2
(0.147MPa) → running frequency 54Hz (54Hz + OFF)
5 min.
30 sec.
42Hz+OFF
30Hz+OFF
0 pulses
H tap (H+ON)
H tap (H+ON)
ON
ON
ON/OFF
(Td protection control)
(Td protection control)
Function Urban Multi "MX1R, ME1R Series" Using R-407C
PACD011001C2
30 sec.
4 min. 30 sec.
PI control
∗32~106 Hz + OFF
SH control
0 pulses
(Initial opening 150 pulses)
H tap
H tap
(H+ON)
(H+ON)
ON/OFF
OFF
(LP protection control)
ON/OFF
ON/OFF
(Td protection control)
30 sec.
4 min. 30 sec.
116Hz+OFF
0 pulses
150 pulses
H tap (H+ON)
OFF
ON/OFF
(LP protection control)
ON/OFF
ON/OFF
(Td protection control)
- Quick Links:
- Mx1 Series
Hide quick links:
Table of Contents
Troubleshooting
