Mitsubishi Electronics R410A Test run, Before test run, Refrigerant collecting Pump down

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7. Test run

7.1. Before test run

sAfter completing installation and the wiring and piping of the indoor and outdoor units, check for refrigerant leakage, looseness in the power supply or control wiring, wrong polarity, and no disconnection of one phase in the supply.

sUse a 500-volt M-ohm tester to check that the resistance between the power supply terminals and ground is at least 1 MΩ.

sDo not carry out this test on the control wiring (low voltage circuit) termi-

nals.

Warning:

Do not use the air conditioner if the insulation resistance is less than 1 MΩ.

Insulation resistance

After installation or after the power source to the unit has been cut for an extended period, the insulation resistance will drop below 1 MΩ due to refrigerant accumulat- ing in the compressor. This is not a malfunction. Perform the following procedures.

1.Remove the wires from the compressor and measure the insulation resistance of the compressor.

2.If the insulation resistance is below 1 MΩ, the compressor is faulty or the resist- ance dropped due the accumulation of refrigerant in the compressor.

3.After connecting the wires to the compressor, the compressor will start to warm up after power is supplied. After supplying power for the times indicated below, measure the insulation resistance again.

•The insulation resistance drops due to accumulation of refrigerant in the com- pressor. The resistance will rise above 1 MΩ after the compressor is warmed

up for four hours.

(The time necessary to warm up the compressor varies according to atmos- pheric conditions and refrigerant accumulation.)

•To operate the compressor with refrigerant accumulated in the compressor, the compressor must be warmed up at least 12 hours to prevent breakdown.

4.If the insulation resistance rises above 1 MΩ, the compressor is not faulty.

Caution:

•The compressor will not operate unless the power supply phase connection is correct.

•Turn on the power at least 12 hours before starting operation.

-Starting operation immediately after turning on the main power switch can result in severe damage to internal parts. Keep the power switch turned on during the op- erational season.

sThe followings must be checked as well.

•The outdoor unit is not faulty. LED on the control board of the outdoor unit flash when the outdoor unit is faulty.

•Both the gas and liquid stop valves are completely open.

7.2. Test run

7.2.1.Using remote controller

Refer to the indoor unit installation manual.

•Be sure to perform the test run for each indoor unit. Make sure each indoor unit operates properly following the installation manual attached to the unit.

•If you perform the test run for all indoor units at once, you cannot detect any

erroneous connection, if any, of the refrigerant pipes and the connecting wires. * The compressor operation is not available for 3 minutes at least after the

power is supplied.

•The compressor can emit noise just after turn on the power supply or in case of low outside air temperature.

About the restart protective mechanism

Once the compressor stops, the restart preventive device operates so the compres- sor will not operate for 3 minutes to protect the air conditioner.

7.2.2.Using SW3 in outdoor unit

Note:

In case of the test run from outdoor unit, all indoor units operate. Therefore, you can not detect any erroneous connection of refrigerant pipes and the con- necting wires. If it aims at detection of any erroneous connection, be sure to carry out the test run from remote controller with reference to “7.2.1 Using remote controller”.

SW3-1

ON

Cooling operation

SW3-2

OFF

 

SW3-1

ON

Heating operation

SW3-2

ON

 

* After performing the test run, set SW3-1 to OFF.

•A few seconds after the compressor starts, a clanging noise may be heard from the

inside of the outdoor unit. The noise is coming from the check valve due to the small difference in pressure in the pipes. The unit is not faulty.

The test run operation mode cannot be changed by DIP switch SW3-2 during the test run. (To change the test run operation mode during the test run, stop the test run by DIP switch SW3-1. After changing the test run operation mode, resume the test run by switch SW3-1.)

7.3. Refrigerant collecting (Pump down)

Before removing air conditioners for transfer to another location, always close the stop valve (for both liquid and gas pipes) located at the outdoor unit, then remove the indoor and outdoor units. At this time, the refrigerant in the indoor unit will be dis- charged. To minimize the refrigerant discharged, a pump down operation is required. This operation collects the refrigerant present inside the air conditioner and sends it into the heat exchanger located in the outdoor unit.

Pump down procedure

1Operate all indoor units in cooling mode and check that the operation mode has changed to “COOL”. (Set the units so that cooling operation mode is activated during the pump down operation (when the TEST RUN button is pressed).)

2Connect a gauge manifold valve (with pressure gauge) to the stop valve of the gas pipe, to enable measurement of refrigerant pressure.

3After setting the outdoor service switch SW3-2 to OFF, set the switch SW3-1 to

ON. (The unit will start in cooling mode.)

4After the cooling operation has been carried out for approximately five minutes, set the outdoor service switch SW2-4 (pump down switch) from OFF to ON.

5Close the stop valve on the liquid pipe, with the cooling operation still ON. (Pump down operation will start.)

6When the reading of the pressure gauge reaches 0 to 0.1 MPa [14.5 PSIG] or when approximately 5 minutes have elapsed following the start of the pump down operation, fully close the stop valve on the gas pipe and stop the air conditioner by setting the switch SW3-1 to OFF immediately.

7Set the outdoor service switch SW2-4 from ON to OFF.

8Remove the gauge manifold valve and put the cap back onto each stop valve.

Note:

1Never carry out pump down operation if the amount of refrigerant inside the indoor unit is larger than the amount of charge-less refrigerant. Carrying out a pump down operation when the amount of refrigerant ex- ceeds the amount of charge-less refrigerant will cause an extreme pres-

sure rise and may result in an accident.

2Do not continue to operate for a long time with the switch SW2-4 set to ON. Make sure to switch it to OFF after pump down is completed.

3Test run can be carried out when the test run switch SW3-1 is ON. Switch SW3-2 is used to operating mode selection. (On: Heating, OFF: Cooling)

4Time required for a pump down operation is three to five minutes after the

stop valve on the liquid pipe has been closed. (It depends on the ambient temperature and amount of refrigerant inside the indoor unit.)

5Ensure that the reading of the pressure gauge does not drop below 0 MPa (0 PSIG). If it drops 0 MPa [0 PSIG] (i.e. vacuum is created), air will be drawn into the unit if there are any loose connections.

6Even if the reading of the pressure gauge does not drop below 0 MPa [0 PSIG], always stop the pump down operation within approximately five min- utes after the stop valve on the liquid pipe has been fully closed.

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Contents PUMY-P·NHMU -BS Confirmation of parts attached ContentsSafety precautions Installation location When installing multiple outdoor units Ventilation and service spaceWhen installing a single outdoor unit Windy location installation Installing the outdoor unitInstalling the refrigerant piping Precautions for devices that use R410A refrigerantConnecting pipes Fig Stop valve opening method Refrigerant pipe airtight testing methodRefrigerant piping Fig Additional refrigerant charge Drainage piping workElectrical work Wiring transmission cables Control box and connecting position of wiring FigSchematic Drawing of Wiring Example Fig Wiring of main power supply and equipment capacityNET Remote Controller MA Remote Controller Refrigerant collecting Pump down Test runBefore test run Test runCuestiones previas a la instalación ContenidoConfirmación de las piezas incluidas Medidas de SeguridadAntes de realizar las pruebas de funcionamiento Dimensiones exteriores Unidad exterior FigLugar de instalación Antes de la instalación eléctricaCuando instale varias unidades exteriores Ventilación y espacio de servicioCuando se instala una unidad exterior simple Instalación de la unidad exterior Instalación de la unidad exteriorInstalación de los tubos del refrigerante Instalación en lugares expuestos al vientoTubos de conexión Fig Método de abertura de la válvula de retención Tubos de refrigerante FigPrueba de fuga de gas del tubo de refrigerante Cuidado Tubería de drenajeTrabajo eléctrico Carga adicional de refrigeranteTendido de cables de transmisión Caja de control y posición de conexión de los ca- bles FigDibujo esquemático del cableado ejemplo Fig Controlador remoto M-NET Controlador remoto MARecuperación de refrigerante vaciado Prueba de funcionamientoAntes de realizar las pruebas Prueba de funcionamientoVérification des pièces livrées Avant l’installationAvant l’installation déplacement IndexAvant la marche d’essai Emplacement d’installationAvant l’installation électrique Dimensions extérieures Appareil extérieur FigLors de l’installation de plusieurs appareils extérieurs Ventilation et espace de serviceLors de l’installation d’un seul appareil extérieur Installation de l’appareil extérieur Installation de l’appareil extérieurInstallation de la tuyauterie du réfrigérant Installation à un endroit exposé au vent100 120 Connexion des tuyaux FigØ9,52 3/8 Ø15,88 5/8 C, d, e, f Mm inch Numéro de modèle Couple de serrageComment ouvrir la vanne d’arrêt Mise en place des tuyaux de réfrigérant FigTest d’étanchéité des tuyaux de réfrigérant Précaution Installations électriquesMise en place du tuyau d’écoulement Charge supplémentaire de réfrigérantMise en place des câbles de transmission Schéma du câblage exemple Fig Commande à distance M-NET Commande à distance MARécupération du réfrigérant Aspiration Utilisation de la télécommandeMarche d’essai Marche d’essaiBG79U872H02

R410A specifications

Mitsubishi Electronics R410A is a highly regarded refrigerant widely used in modern HVAC systems, particularly air conditioning units. This hydrofluorocarbon (HFC) refrigerant has gained popularity due to its environmental benefits and performance characteristics that meet the demands of contemporary cooling solutions.

One of the main features of R410A is its high energy efficiency. The refrigerant operates at a higher pressure compared to its predecessor, R22, which allows for smaller, more compact systems. This higher efficiency translates to lower energy consumption during operation, making R410A an environmentally friendly option that contributes to reducing greenhouse gas emissions. The energy savings not only benefit the environment but also reduce operational costs for end-users.

R410A also boasts excellent cooling capacity. Its thermodynamic properties enable effective heat exchange, making it suitable for various applications ranging from residential air conditioners to commercial chillers. The ability to maintain effective cooling performance even at high outdoor temperatures is a crucial characteristic, especially in warmer climates where high reliability is essential.

In terms of safety, R410A is classified as non-flammable and has a low toxicity level, making it a safer choice for use in both residential and commercial installations. It carries an ozone depletion potential (ODP) of zero, aligning with global efforts to phase out substances that deplete the ozone layer. As such, it complies with various international environmental regulations, ensuring that users are contributing to a sustainable future.

Mitsubishi Electronics integrates advanced technologies in their heating and cooling systems that utilize R410A. Features such as variable speed compressors and advanced control systems optimize performance, enhancing both comfort and energy efficiency. Additionally, the systems are designed to offer quiet operation, catering to users who prioritize noise reduction in their living or working environments.

In conclusion, Mitsubishi Electronics R410A refrigerant presents a combination of high energy efficiency, excellent cooling capacity, and safety attributes, solidifying its role as a vital component in contemporary HVAC technology. By utilizing R410A, Mitsubishi Electronics demonstrates its commitment to sustainability and performance, offering solutions that cater to the diverse needs of consumers while minimizing environmental impact.
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