Mitsubishi Electric Split-Type Air Conditioners Installation Manual

1. Before Installation

Safety First: Always observe safety precautions and instructions. Store this manual with the operating instructions for future reference. Ensure consent is obtained from the power supply authority before connecting the equipment. Never attempt to install the unit yourself; consult a qualified installer. Follow all instructions in the manual to prevent fire, electric shock, unit falling, or water leakage. Use appropriate protective equipment and tools. Install the unit securely in a place that can bear its weight. Do not alter the unit. Use an exclusive circuit for the air conditioner and perform electrical work according to the installation manual. Ensure proper grounding, avoiding connection to gas pipes, water pipes, lightning rods, or telephone grounds. Do not damage wires. Shut off the main power before working on the indoor P.C. board or wiring. Use specified wires and connect them securely to avoid stress on the terminal block. Do not install in places where flammable gas may leak. Avoid intermediate power cord connections or extension cords, and do not connect multiple devices to one outlet. Use only provided or specified parts for installation. Ensure the power supply plug and outlet are clean and the plug is fully inserted. Securely attach electrical covers and service panels to prevent dust and water ingress, which could cause fire or electric shock. Ensure only the specified refrigerant (R410A) enters the refrigerant circuit to prevent abnormal pressure rise. Do not discharge refrigerant into the atmosphere. Check for leaks after installation and ventilate the room if leaks occur. Use appropriate tools and piping materials for R410A due to its higher pressure. Stop the compressor before disconnecting refrigerant pipes during pump down. Securely connect refrigerant pipes before starting the compressor. Fasten flare nuts with a torque wrench as specified. Install according to national wiring regulations. Be cautious when opening or closing valves at low temperatures to avoid refrigerant spurts.

Caution: Depending on the installation area, install a Ground Fault Interrupt (GFI) circuit breaker. Perform drainage and piping work securely to prevent water leakage and damage. Do not touch the air inlet or aluminum fins of the outdoor unit. Avoid installing the outdoor unit where small animals may live, as they can damage electrical parts and cause malfunctions.

2. Selecting the Installation Location

Indoor Unit: Choose a location with unobstructed airflow where cool or warm air can spread throughout the room. Mount on a rigid wall to minimize vibration. Avoid direct sunlight and locations exposed to heat or steam sources. Ensure easy drainage and a distance of at least 3 ft. (1 m) from TVs and radios to prevent interference. Place it away from fluorescent and incandescent lights for optimal remote control operation. Ensure the air filter can be removed and replaced easily.

Remote Controller: Select a convenient and visible location, out of reach of children. Position it about 4 ft. (1.2 m) above the floor and check for signal reception ('beep' or 'beep beep' tone). Note that inverter-type fluorescent lamps may interfere with the remote control signal.

Outdoor Unit: Install where it is not overly exposed to strong winds, which can lengthen defrosting time. Ensure good, dustless airflow. Avoid locations where operation sound or air discharge may annoy neighbors. Use a rigid wall or support to reduce operational sound and vibration. Ensure there is no risk of combustible gas leakage. Secure the unit legs if installed high above the ground. Maintain a distance of at least 10 ft. (3 m) from TV or radio antennas. Install the unit horizontally. In areas with heavy snow, install a canopy, pedestal, and/or baffle boards. For increased efficiency, avoid continuous direct sunlight and excessive water. When operating in low outside temperatures, avoid installing the unit where its air inlet/outlet side faces direct wind. Install with the air inlet facing the wall and a baffle board on the air outlet side. Avoid locations prone to trouble, such as where flammable gas could leak, where there is excessive machine oil in the air, where oil is splashed or the area is filled with oily smoke (e.g., cooking areas), salty places, areas with sulfide gas generation (hot springs, sewage), or areas with high-frequency or wireless equipment. Avoid locations with high levels of VOCs which may cause chemical cracking.

3. Specifications

This section details the electrical specifications for indoor and outdoor units, including power supply, circuit ampacity, fan motor ratings, and compressor ratings for various models (MSZ-GS06NA, MSZ-GS09NA, MSY-GS09NA, MSZ-GS12NA, MSY-GS12NA, MSZ-GS15NA, MSY-GS15NA). It also covers refrigerant pipe specifications, including pipe diameter, minimum wall thickness, insulation thickness, and limitations on pipe length and height difference. For pipe lengths exceeding 25 ft. (7.5 m), additional refrigerant (R410A) charge is required.

4. Installation Diagram

This section provides a visual guide to the installation process, detailing the accessories included (installation plate, wireless remote controller, felt tape, remote controller holder, screws, batteries, air cleaning filters) and field-supplied parts (connecting wire, extension pipe, wall hole sleeve, wall hole cover, pipe attachment strap, screws, piping tape, putty, drain hose, refrigerant oil, power supply cord). It illustrates the correct placement of components, including the indoor unit, wall hole sleeve, and piping attachments, emphasizing the need for proper sealing of wall holes and insulation of pipes. Diagrams show recommended clearances for the indoor and outdoor units and illustrate correct and incorrect drain piping methods.

5. Indoor Unit Installation

Attaching the Installation Plate: Securely attach the installation plate horizontally to a wall stud using fixing screws. Ensure screws are installed in the indicated holes for stability. For concrete walls, use recessed bolts with appropriate oval holes. If a recessed bolt is too long, replace it with a shorter one.

Drilling: Determine hole locations on the wall and drill a ø 3 in. (75 mm) hole. The outdoor side should be slightly lower than the indoor side. Insert the wall hole sleeve.

Connecting Wires for Indoor Unit: Ensure power is supplied from the outdoor unit as per local codes, possibly requiring a disconnect switch. Remove the panel assembly, corner box, and electrical cover. Process the ground wire and connect it to the ground terminal. Process the indoor/outdoor unit connecting wire and attach it to the terminal block securely, ensuring no mis-wiring. Tighten terminal screws firmly and verify wire fastening. Reinstall covers and panels. Remove necessary parts of the box or corner box according to the piping direction. Ensure connecting wires are kept away from the TV antenna wire.

6. Pipe Forming and Drain Piping

Pipe Forming: Place the drain hose below the refrigerant piping, ensuring it is not crowded or bent. Do not pull the hose when applying tape. Wrap the drain hose with insulation material if it passes through a room. For left or left-rear piping, reattach the drain hose and drain cap. Apply felt tape from the end, overlapping by one-third the tape width, and use a bandage stopper. Pull out the drain cap and drain hose from the back of the indoor unit. Insert the drain cap into the drain pan and then insert the drain hose securely. For rear or bottom piping, apply piping tape and insert the piping and drain hose into the wall hole sleeve. Attach the indoor unit and check for secure attachment. For right piping, ensure wiring is completed and the conduit cover is installed. Shift piping and drain hose to the left side, apply piping tape, and insert into the wall hole sleeve. Attach the indoor unit and check for secure attachment.

Drain Piping: Wrap the extension drain hose with insulation if it passes through a room. Ensure the drain hose points downward. If the provided hose is too short, connect it with a field-supplied drain hose. When connecting to a hard vinyl chloride pipe, insert it securely. Do not place the drain pipe directly in a drainage ditch where ammonia or sulfuric gas may be generated, as this can cause odor and corrosion. Avoid drain piping configurations that allow water to accumulate or the tip of the drain hose to be submerged in water.

7. Outdoor Unit Installation

Connecting Wires for Outdoor Unit: Remove the service panel and conduit cover. Attach conduit connectors to the conduit plate. Connect ground wires of the indoor/outdoor unit connecting wire and power supply cord to the TB support. Attach indoor/outdoor unit connecting wire and power supply cord to the terminal block securely. Tighten terminal screws firmly. Install the conduit cover and service panel securely. Ensure the earth wire is longer than others and leave slack in connecting wires for future servicing.

Flare Connection: Cut copper pipe straight with a pipe cutter and remove burrs. Attach flare nuts to the pipes. Perform flaring work using the appropriate tool and dimensions specified in the table. Check the flared work for defects and repeat if necessary. Ensure the inside of the flare is smooth and without scratches.

Pipe Connection: Fasten flare nuts with a torque wrench as specified. Avoid over-tightening. Wrap insulation around the piping to prevent burns or frostbite. Connect both liquid and gas pipings to the indoor unit, applying a thin coat of refrigeration oil on flared ends only. Align the center and tighten flare nuts by hand initially. Use the torque table as a guideline and tighten using two wrenches. Connect pipes to the stop valve pipe joint of the outdoor unit following the same procedure. Ensure refrigerant pipes are securely connected before starting the compressor.

Insulation and Taping: Cover piping joints with pipe cover. Insulate the piping, including valves, for the outdoor unit side. Apply piping tape starting from the connection on the outdoor unit. Use additional insulation if piping passes through areas with high temperature and humidity to prevent condensation.

8. Purging Procedures, Leak Test, and Test Run

Purging Procedures and Leak Test: Remove service port caps from stop valves. Connect the gauge manifold to the ports of the stop valves. Evacuate the system to 500 microns using a micron gauge. Break the vacuum with Nitrogen (N2) to 0 PSIG. Perform a 30-minute rise test and ensure the system holds 500 microns for at least 1 hour. Fully open the valve stems of all stop valves. Charge additional refrigerant if needed, slowly and with liquid refrigerant. Remove gauge manifolds, replace service port caps, and tighten.

Test Run: Insert the power supply plug or turn on the breaker. Press the E.O. SW (Emergency Operation Switch) for COOL or HEAT operation. The test run will last for 30 minutes. If the upper lamp blinks, inspect the indoor/outdoor unit connecting wire. After the test run, emergency COOL mode will start. Press the E.O. SW several times to turn off the unit. Check remote signal reception by pressing the OFF/ON button on the remote controller. The compressor will not operate for 3 minutes after shutdown to protect the unit.

Auto Restart Function: The unit is equipped with an auto restart function that resumes operation in the previous setting after a power interruption. This function can be deactivated if unnecessary; consult a service representative. Explain this function to the user.

Explanation to the User: Use the operating instructions to explain the unit's functions, including remote controller operation, filter removal, cleaning, and precautions. Recommend the user read the operating instructions carefully.

9. Relocation and Maintenance

Removing and Installing the Panel Assembly: Remove screws attaching the panel assembly and detach the assembly, starting from the bottom. For installation, reverse the removal procedure. Press indicated positions to attach the assembly securely.

Removing the Indoor Unit: Detach the bottom of the indoor unit from the installation plate. Release the corner parts and pull downward and forward. Alternatively, remove the front panel and use hexagonal wrenches to push up on the square holes on the sides to release the hooks.

Pumping Down: To relocate or dispose of the air conditioner, pump down the system to prevent refrigerant release. Connect the gauge manifold to the service port of the stop valve on the gas pipe side. Close the stop valve on the liquid pipe side. Almost completely close the stop valve on the gas pipe side until the pressure gauge shows 0 psi. Start emergency COOL operation. After 15 seconds, connect the power supply and press the E.O. SW once. Fully close the gas pipe stop valve when the pressure gauge shows 0 to 0.1 psi. Stop the emergency COOL operation. Warning: Do not execute pump down with the compressor if the refrigeration circuit has a leak. Stop the compressor before disconnecting refrigerant pipes.

10. Connecting the Interface/Connector Cable to the Air Conditioner

Connect the INTERFACE/CONNECTOR CABLE to the indoor electronic control P.C. board using the connecting cable. Do not bundle the connecting cable with power supply cords or other wires. Keep the connecting cable away from these wires. Store the thin part of the connecting cable where it cannot be touched. Attach the cable clamp provided with the interface to the thick part of the connecting cable. Close the cover of the indoor control P.C. board carefully, ensuring the thin part of the connecting cable is not caught. Reinstall the panel and corner box. Warning: Securely fix the connecting cable to prevent electric shock, fire, or malfunction.