Mitsumi electronic MXZ-ANA Manuale Utente

3-2. EXPANSION VALVE CONTROL (LEV CONTROL)

Linear expansion valve (LEV) is controlled by “Thermostat ON” commands given from each unit.

Indoor unit status

LEV opening

Stop of all indoor unit

Opening before stop → 500 pulses in 15 minutes

When outdoor unit is operating,

some indoor units stop and some

operate.

COOL: 5 pulses (full closed)

HEAT: (MXZ-2A/3A30NA/2B): 140 pulses (slightly opened)

: (MXZ-3A30NA-

/4A/3B/4B): 100 → 59 pulses

Thermostat OFF in COOL or DRY

mode

When the outdoor unit operates (When the other indoor unit operates): 5 pulses

When outdoor unit stops. (When the other indoor unit stops or thermo OFF):

Maintain LEV opening before stop → 500 pulses in 15 minutes

Thermostat ON in COOL or DRY

mode

• LEV opening for each indoor unit is determined by adding adjustment according to the

number of operating unit and the capacity class to standard opening, based on the

operation frequency:

e.g.) Opening 130 pulses in standard opening 1 → Minimum 80 pulses/Maximum 205

pulses (Capacity code 4 at 1 unit operation) (Capacity code 1 at 3 units operation)

• After starting operation, adjustment according to intake super heat, discharge tempera-

ture is included in standard opening. 1

NOTE: LEV opening in each frequency at DRY operation and COOL operation is the

same. However, velocity and compressor operation frequency controls are differ-

ent. See 3-3. OPERATIONAL FREQUENCY RANGE

(As far as the indoor unit velocity control goes, refer to DRY operation in MICRO-

PROCESSOR CONTROL in indoor unit.)

Thermostat OFF in HEAT mode

• When the outdoor unit operates. (When the other indoor unit operates): 140 pulses

• When the outdoor unit stops. (When the other indoor unit stops or thermo OFF): Main-

tain LEV opening before stop → 500 pulses in 15 minutes “

Thermostat ON in HEAT mode

• LEV opening for each indoor unit is determined by adding adjustment according to the

number of operating unit and the capacity class to standard opening, based on the

operation frequency:

e.g.) Opening 120 pulses in standard opening 1 → Minimum 70 pulses/Maximum 165

pulses (Capacity code 4 at 1 unit operation) (Capacity code 1 at 3 units operation)

• After starting operation, opening becomes the one that adjustment according to dis-

charge temperature was added to basic opening. 1 “

1 LEV opening when the outdoor unit is operating: Upper limit 500 pulses, Lower limit 53 pulses (MXZ-2A/3A30NA/2B)/59

pulses (MXZ-3A30NA-

/4A/3B/4B).