Mitsubishi Electric MXZ-2C20NA2 Notice D'installation page 7

4-2. GAS CHARGE
Perform gas charge to unit.
1) Connect gas cylinder to the service port of stop valve.
2) Perform air purge of the pipe (or hose) coming from refrigerant gas cylinder.
3) Replenish specified amount of the refrigerant, while operating the air conditioner for cooling.
Note:
In case of adding refrigerant, comply with the quantity specified for the refrigerating cycle.
CAUTION:
When charging the refrigerant system with additional refrigerant, be sure to use liquid refrigerant.
Adding gas refrigerant may change the composition of the refrigerant in the system and affect
normal operation of the air conditioner. Also, charge the liquid refrigerant slowly, otherwise the
compressor will be locked.
To maintain the high pressure of the gas cylinder, warm the gas cylinder with warm water (under
104°F (40°C)) during cold season. But never use naked fire or steam.
4-3. REMOVING THE MAINTENANCE PANEL
The setting of Dip Switch on the outdoor controller board can be changed
without removing the front panel.
Follow the procedures below to remove the maintenance panel and set
the Dip Switch.
1) Remove screw(s) which fix the maintenance panel.
2) Remove the maintenance panel, and perform necessary settings.
3) Install the maintenance panel.
Note:
Make sure to fix the maintenance panel securely. Incomplete installation
could cause malfunction.
4-4. LOCKING THE OPERATION MODE OF THE AIR CONDITIONER (COOL, DRY, HEAT)
• Description of the function:
With this function, once the operation mode is locked to either COOL/DRY mode
or HEAT mode, the air conditioner operates in that mode only.
* Changing the setting is required to activate this function. Please explain about
this function to your customers and ask them whether they want to use it.
[How to lock the operation mode]
1) Be sure to turn off the main power for the air conditioner before making the
setting.
2) Set the "3" of SW1 on the outdoor controller board to ON to enable this function.
3) To lock the operation mode in COOL/DRY mode, set the "4" of SW1 on the
outdoor controller board to OFF. To lock the operation in HEAT mode, set the
same switch to ON.
4) Turn on the main power for the air conditioner.
4-5. LOWERING THE OPERATION NOISE OF THE OUTDOOR UNIT
• Description of the function:
With this function, the operating noise of the outdoor unit can be lowered by reducing the operation load, for example, during nighttime in COOL mode. However,
please note that the cooling and heating capacity may lower if this function is activated.
* Changing the setting is required to activate this function. Please explain about this function to your customers and ask them whether they want to use it.
[How to lower the operating noise]
1) Be sure to turn off the main power for the air conditioner before making the setting.
2) Set the "5" of SW1 on the outdoor controller board to ON to enable this function.
3) Turn on the main power for the air conditioner.
Model
MXZ-2C20NA2
Union
Union
Indoor
unit
Union
Union
Refrigerant gas
cylinder
operating valve
Gauge manifold
(for R410A)
valve (for R410A)
Refrigerant gas cylinder for R410A with siphon
Refrigerant (liquid)
Electronic scale for refrigerant charging
Maintenance panel
LED
SW1
SW871
SW1
ON
SW2
1 2 3 4 5 6
COOL/DRY
Lower the operating noise
Indoor unit
A – B
Stop valve
Liquid
pipe
Outdoor
unit
Stop valve with
Gas
service port
pipe
Charge hose
(for R410A)
SW1
ON
1 2 3 4 5 6
HEAT
En-6