Hitachi Split Unit Inverter Air Conditioner

Introduction

This manual provides essential information for the correct installation of the Hitachi Split Unit Inverter Air Conditioner Outdoor Unit. Please read this manual carefully before installation and keep it for future reference. The unit contains refrigerant, and the quantity is adequate for pipes up to 30m. For longer pipes, additional refrigerant may be required. Refer to the piping instructions for specific details.

Important Note: Hand over this manual to workers involved in transportation, handling, piping work, electrical wiring, test run, and finally to the customer.

This product is a general air-conditioner and should not be used for special purposes such as food, animal, plant, or precision machinery storage.

Locations to Avoid for Installation:

• Locations with flammable gas and airborne grease (risk of fire, machine deformation, erosion, damage).
• Locations with airborne grease (including engine oil) and flammable gases.
• Locations with sulfur gas, such as hot springs.
• Coastal areas and locations with higher salinity.
• Locations with high acidity or alkalinity.
• Near medical instruments that generate electromagnetic waves, to avoid malfunction.

Temperature Ranges of Use:

DB: Dry-bulb temperature/WB: Wet-bulb temperature

Safety Precautions

Warning: Failure to follow these instructions may cause severe injury.

• Install the unit according to the instructions in this manual. Incorrect installation can lead to water leakage, electric shock, or fire.
• Use special tools and piping materials for R410A refrigerant. R410A operates at a higher pressure than R22, and incorrect materials can cause explosions.
• Do not install in locations where flammable gas may be present.
• Ensure the unit is installed in a location that can fully support its weight to prevent it from falling.
• Do not climb on or place objects on the unit to prevent collapse or overturning.
• Ensure no refrigerant leaks. R410A is non-flammable, but leaks can cause oxygen insufficiency in enclosed spaces.
• Use only the specified refrigerant (R410A) and refrigeration oil (Ze-GLES RB74). Using other types may cause machine failure or explosion.
• Do not heat the machine or any parts, as it maintains high pressure.
• Remove flammable objects before welding operations.
• Wear leather gloves when handling refrigerant to prevent frostbite.
• Use only non-flammable cleaning agents for refrigerant recovery.
• Ensure adequate ventilation in confined spaces to prevent oxygen insufficiency.
• Recover cleaning agents after use; do not release CFCs into the atmosphere.

Precautions for Electrical Works:

• All electrical work must be performed by a qualified electrician, following national regulations and this manual. Use an individual circuit for the air conditioner.
• Use wires of the correct types and gauges. Ensure connections are secure to prevent overheating.
• Wires should be protected from external damage.
• Ensure both indoor and outdoor units are properly earthed. Do not earth to gas pipes, water pipes, or phone lines.
• Install an earth leakage circuit breaker (ELCB).
• Disconnect the power supply before performing any wiring or electrical inspections.
• Prevent wires from being bitten by animals by keeping them away from potential hazards.
• Avoid jamming wires when installing the panel cover.

Handling

Carry the outdoor unit in its original packing to the installation location whenever possible.

Before Installation:

• This unit uses HFC refrigerant (R410A), which does not damage the ozone layer.
• R410A operates at 1.4 times higher pressure than ordinary refrigerants and is more sensitive to water, oxides, and grease. Use only the specified refrigeration oil (Ze-GLES RB74).
• Ensure that no water, impurities, non-R410A refrigerant, or non-Ze-GLES RB74 refrigeration oil enter the system.
• Use specific tools for filling R410A refrigerant and Ze-GLES RB74 refrigeration oil, as connectors and cap nuts differ from other refrigerants.

Tools and Gauges:

Refer to the table for interchangeability with R22 and R407C, and specific tools required for R410A.

• Copper pipe cutter: For cutting and deburring pipes.
• Pipe expander: For expanding the flare of refrigerant pipes.
• Pipe bender: For bending refrigerant pipes.
• Welder: For welding refrigerant pipes.
• Nitrogen: For preventing oxidation and air-tightness testing.
• Torque wrench: For locking cap nuts.
• Refrigerant cylinder: Identified by color (R410A: Pink, R407C: Brown). Use liquid refrigerants only.
• Vacuum pump: For vacuum drying.
• Manifold gauge set: For confirming vacuum status and refrigerant filling pressure.
• Filling hose: For filling refrigerants.
• Refrigerant filling scale: For measuring refrigerant filling level.
• Refrigerant leak detector: For testing refrigerant leakage.

Pipe Specifications:

• Flare Size: Refer to the diagram for dimensions.
• Pipe Diameter and Wall Thickness: Ensure correct wall thickness for R410A piping according to the design pressure.
• Connector Selection: Wall thickness of connectors must match the design pressure. Use appropriate tubing for minimum wall thickness. Cap nut sizes may also change.

Outdoor Unit Accessories

Verify the following accessories before installation:

• Special Washers (4 pcs): For securing the mounting board.
• Drain pipe (1 pc): For draining condensate from the bottom.

Verification of Combined Capacity

Select the quantity and capacity of indoor units for the outdoor unit as shown in the table:

Attention:

The unit will not operate for the first four hours after power connection (error code "d1-22"). To bypass this protection, connect power to both units, wait 30 seconds, and then press PSW1 and PSW3 switches on the outdoor unit's mainboard simultaneously for three seconds.

Outdoor Unit Installation

Cautions:

• Do not install in locations with flammable gases, salt, sulfur, acid, or alkaline environments.
• Do not install near instruments producing electromagnetic waves.
• Keep machinery generating electromagnetic waves at least 3 meters away from the air conditioner.
• Do not install the outdoor unit indoors.

Installation Space:

Maintain adequate space around the outdoor unit for maintenance. Refer to the diagrams for specific clearances for standalone and multiple unit installations.

Installation Locations:

• Choose dry and well-ventilated locations.
• Avoid direct sunlight and heat sources. Use a shade if necessary.
• Ensure unit operation noise does not disturb neighbors.
• Do not direct airflow towards ornamental plants or neighbors' windows.
• Prevent dust or scrap paper from entering the heat exchanger. Use a wind guard if necessary.
• Avoid installing in places with headwind; use a wind guard if strong winds are expected.

Installation in Places with Strong Winds:

• Do not face the air outlet towards headwinds, as this can damage the unit.
• When installing with the air outlet facing headwinds, consider using an optional wind guard.
• When there is a wall, ensure at least 600mm clearance from the wall.

Attention: Strong winds blowing towards the air outlet can cause the fan to rotate in reverse and become damaged.

Installation

Securing the Unit:

• Securely fix the outdoor unit on the foundation using anchor bolts to prevent collapse, shaking, or noise due to uneven installation.
• Anchor bolt size: M10.
• Verify drainage and drain pipe installation. Ensure good drainage and avoid installing the unit where dripping water could cause hazards.
• If using frames with narrower legs than the outdoor unit, add a board under the unit's legs for adequate support.

Example of Fixing Stand with Anchor Bolts:

Illustrates the process of fixing the stand with anchor bolts, noting the need to cut off section A for easier pipe cover removal.

Recommended Board Size:

SPHC material, 4.5mm thickness. Dimensions provided.

Maintaining Space for Piping:

Ensure adequate space for piping connections.

Frame Leg Width vs. Outdoor Unit Leg Width:

Diagrams show clearances and the need for support boards if the frame legs are narrower.

Piping

3-1 Refrigerant Pipe Installation:

Requirements for pipe diameter, length, and lapse height between indoor and outdoor units are detailed.

• System Example: Diagram shows a typical setup with one outdoor and multiple indoor units.
• Total Pipe Length: L0 + L1 + L2.
• Max. Pipe Length (actual): Lt.
• Max. Lapse Height: H1 (outdoor unit to indoor unit), H2 (between indoor units).
• Max. Pipe Length between Branch Pipes and Indoor Units: L1, L2.
• Branch Pipe Selection: Refer to MW-NP282A.

Cautions:

• Refrigerant and refrigeration oil pipes must have the same length and route.
• Branch pipes should be located near the indoor unit.

Refrigerant Pipe Size:

Details pipe sizes for indoor and outdoor units for gas and liquid sides.

Precautions for Installing Refrigerant Pipes:

• Ensure pipes are free of water and dust. Cut with a copper pipe cutter and clean with nitrogen or compressed air. Do not use a saw or whetstone.
• Prepare suitable refrigerant pipes onsite.
• Protect pipe ends when penetrating walls or when pipes are not in use.
• Connect indoor units using the optional branch pipe kit only. Do not use connectors.
• Maintain level when fixing branch pipes.
• Fix pipes with clamps outside the insulation layer or add cushions between clamps and pipes.

Fixing Branch Pipes:

Diagrams illustrate correct and incorrect methods for fixing branch pipes.

Precautions for Releasing Pressure from Pipe Union:

Release pressure from the fluid interceptor valve and gas interceptor valve as instructed.

Pipe Removal Direction

Pipes can be installed in four locations. Remove the appropriate cover and install the pipe through the hole. Break covers with a screwdriver or hammer as needed.

• Size Cover Flash: Wrap wires and pipes with insulation sheets after removing covers.
• Front and Right Piping
• Bottom Piping
• Rear Piping: Remove the rear piping cap next to the bottom cover.

Guidelines for Opening Panel Cover:

Instructions for removing the panel cover, including pressing and sliding.

Pipe Connection and Insulation

• Ensure the interceptor valve of the outdoor unit is shut.
• Connect pipes between indoor and outdoor units. Lock pipe fittings with two wrenches at the specified torque, applying refrigeration oil to the flare. Check for leaks. Fill pipes with nitrogen before welding.
• Fix pipes appropriately, avoiding weak walls or ceilings to prevent vibration and noise.
• Re-confirm there are no leaks after piping.
• Wrap pipefittings and pipe ends with insulation sheets and secure with plastic tape.

Interceptor Valve on Outdoor/Indoor Unit:

Illustrates the location and operation of interceptor valves. Torque specifications for locking are provided.

Air-tightness Test:

• Shut the interceptor valve spools before the test.
• Fill pipes with air or non-flammable gas (not oxygen or toxic gases) to 4.15MPaG. Release gas after the test.

Evacuation and Refrigerant Filling

Evacuation:

• Refer to the attention plate inside the panel cover for interceptor valve operation details.
• Evacuate from both gas and liquid interceptor valves until pressure is below -0.1MPaG (-750mmHg).
• After evacuation, shut the valve, stop evacuation, and wait one hour to check for pressure rise.
• Use a filling hose and lock the cap nut at 15-16N•m.
• Check for leaks using a leakage detector or bubbles. Do not use bubble liquids containing NH3.

Refrigeration Filling:

• The unit is shipped with refrigerant. Add refrigerant if pipes exceed the design range (refer to page 12).
• Fully open the gas interceptor valve.
• Add refrigerant from the fluid interceptor valve union while the compressor is operating. The fluid interceptor valve opens slightly.
• Fully open the fluid interceptor valve after filling.
• Check for leaks afterwards.

Note: Removing the interceptor valve spool cap may cause gas to pop from the O-ring, which is not a gas leak.

Caution: Do not purge air with refrigerant, as this can lead to refrigerant insufficiency and compressor damage.

Insulation Sheet Wrapping: Wrap pipes and pipe unions with insulation sheets and plastic tape to prevent performance deterioration and condensation.

Pipe Length DIP Switch (DSW) Settings

Adjust DSW2 settings as shown for refrigerant pipe lengths under 5m or over 30m.

Refrigerant Filling Level

Refrigerant Filling Level and Standard Pipe Length:

Table shows filling levels and standard pipe lengths for different models. Tolerance is ±0.1kg.

Calculation of Additional Refrigerant Filling:

Calculate the required quantity of refrigerant for pipe lengths over 30m using the formula: W = (L - l) x P, where L is the total pipe length, l is the standard pipe length, and P is the compensation value (60g/m).

Recovering Refrigerant:

Follow the steps to recover refrigerant from the outdoor unit before relocation:

1. Connect the manifold gauge set to the gas and liquid interceptor valves.
2. Turn on the A/C power.
3. Set DSW1-1 to ON (unit operation starts) and close the liquid interceptor valve. Start refrigerant recovery.
4. When the low pressure reaches -0.01MPaG (-75mmHg), close the gas interceptor valve, set DSW1-1 to OFF (unit operation stops), and shut down the power.

Caution: Ensure pressure does not drop below -0.01MPaG to prevent compressor damage.

Wiring

Electrical Work:

All electrical work must be performed by a qualified electrician according to national regulations.

Wiring Methods:

• Method B: Power supply from the outdoor unit.
• Method C: Individual power supply for the indoor and outdoor units.

Wiring diagrams are provided for both methods.

Precautions:

• Follow indoor unit installation manual instructions for wiring differences.
• Use appropriate wires (0.75-1.25mm², 2C) for operation circuits, with a maximum length of 1,000m.
• Use shielded wires (e.g., KPEV-S) for H-LINK systems and wiring under 100m.
• Ensure proper grounding of shielded wires.
• Maintain a distance of 5-6cm between power lines and operation circuit cables. Keep power sources of A/C and other machines at least 1m apart. Use metal conduit if separation is not possible.

Precautions for H-LINK System Connection:

• The factory setting for unit terminal impedance (DSW5-1) is ON. Disable it (set to OFF) for the second outdoor unit onwards in multi-unit systems. Only one outdoor unit should have terminal impedance ON.
• Use the same type of cables for all units on the H-LINK.

Wiring Connection Port

Follow indoor unit installation manual instructions for the indoor unit wiring connection port.

Precautions for Wiring:

• Keep appropriate distance among terminals and insulate them.
• Do not use terminals for single-core cables.
• Tie cables together with cable ties, separating them from pipes, compressors, and metal frames.
• Fold up cables to ensure adequate length for service.
• Prevent conduits from entering the outdoor unit to avoid contact with the compressor or circulation pipes.

Wiring Indoor and Outdoor Units:

• Connect indoor and outdoor units according to electrical work instructions (p.13).
• Lock terminal block screws with the specified torque.
• Refer to Electrical Equipment Standards for electrical work.
• Warning: Do not connect a 230VAC source to terminal blocks 1 and 2 of the outdoor unit, as this will damage the mainboard.
• Verify power source voltage and capacity.
• Ensure proper earthing (Type 3 method, impedance under 100Ω).
• Disconnect power before wiring or servicing.

Test Run and Handover

5-1 Test Run:

Perform test runs after completing indoor unit installation.

Precautions for Test Running:

• Check insulation impedance (over 1MΩ) using a 500V insulation tester.
• Ensure the outdoor unit interceptor valve is fully open.
• Check for alarm codes on the remote control if the main switch is open phase.
• Check if the oil heater is operating.
• Connect to power supply for at least 12 hours before test run.
• Ensure ambient temperatures meet requirements for cooling function (Indoor: DB21.5°C/WB16°C, Outdoor: DB0°C).
• Connect pressure meters according to piping precautions (p.9).

About Insulation Impedance:

Low insulation impedance can cause the ELCB to trip. Check compressor insulation impedance and other electrical parts. If impedance is low, remove compressor cables, aliment the oil heater for three hours, and re-measure.

Test Run Procedure:

1. Press the Run/Stop and CHECK buttons on the remote control simultaneously for 3 seconds to initiate test run.
2. The LCD display will show "Test Run" and the number of connected indoor units. Check for proper wiring if the unit count is incorrect. Press Run/Stop to start operation.
3. The unit will operate for 2 hours automatically. The protective device remains active.
4. Press the LOUVER button to check deflector response on indoor units with auto-swing.
5. Test Run ends automatically after 2 hours or when Run/Stop is pressed again. An abnormality will be indicated by a blinking operation light and an error code on the remote control display.

Note: If the operation light blinks every 2 seconds, there is a signal transfer error between the indoor unit and remote control.

Note: Giggling sounds from the outdoor unit after power connection or compressor start/stop are normal.

Test Run Checklist

A checklist is provided to verify all aspects of the test run, including fan direction, temperatures, pressures, refrigerant filling level, remote control functions, protective devices, leakage, cleanliness, and valve status.

5-2 Menu Setup

Perform menu setup after the outdoor unit stops. Do not run setup during operation or in check mode.

Menu Setup:

Press the CHECK button to show function selection codes. Run setup according to instructions, using PSW2 and PSW3 as indicated.

External I/O Setup:

Perform external I/O setup after the outdoor unit stops. Follow similar procedures as menu setup.

Note 1: Record the code for each function set during External I/O setup.

Note 2: Settings for each input terminal should be different. Values exceeding the default are invalid.

Connection examples for input and output are provided, along with factory settings and optional components.

6. Error Code Table

This section lists error codes, their causes, and troubleshooting steps. Critical errors (e.g., "EE") indicate potential compressor failure.

• Code 01: Indoor unit protective device activation (float switch).
• Code 02: Outdoor unit protective device activation (except codes 41, 42).
• Code 03: Signal transfer error (indoor to outdoor).
• Code 04: Signal transfer error (inverter).
• Code 05: Phase check error.
• Code 06: Outdoor unit voltage error (under-voltage).
• Code 07: Compressor outlet superheat drops significantly (indoor unit electronic valve locked).
• Code 08: Compressor upper temperature too high (refrigerant insufficiency, leakage, pipe clogging).
• Codes 11-14: Sensor errors (air inlet/outlet, anti-frost, heat exchanger pipe temperature) due to loose, disconnected, or broken wires.
• Code 19: Indoor unit fan motor protection activation.
• Code 20: Compressor upper temperature sensor error.
• Code 22: Outdoor unit air temperature sensor error.
• Code 24: Pipe temperature sensor error.
• Code 31: Indoor/outdoor unit capacity mismatch.
• Code 35: Indoor unit number setup error.
• Code 38: Protection check circuit error (outdoor unit).
• Code 41: Cooling overload (high pressure switch activated).
• Code 42: Heating overload (high pressure switch activated).
• Code 47: Low pressure protection activated.
• Code 48: Overload protection activated (excessive refrigerant, pipe clog, compressor error).
• Code 51: Current check error.
• Code 53: Power module protection activated (inverter error).
• Code 54: Inverter fin temperature sensor error.
• Code 55: Inverter failure.
• Code 57: Outdoor unit fan motor error.
• Code 59: Inverter fin temperature sensor error.
• Code b1: Refrigerant system location error.
• Code EE: Compressor protection error.

Note: Blinking operation light every 2 seconds indicates a signal transfer error.

Note: Check outlet temperature difference between units if it exceeds 10°C for cooling, indicating a potential refrigerant piping problem.

Warning: Do not operate the unit before test run is completed. Check electrical wiring carefully.