The Cooper&Hunter CHML-U36RK4-NG is a powerful inverter outdoor unit from the Nordic Multi Light R32 NG series, designed for multi-zone air-conditioning systems with 2 to 4 compatible indoor units.

With 10.6 kW cooling capacity and 12.0 kW heating capacity, the unit is suitable for larger apartments, private houses, offices and other multi-room spaces where several indoor units can be operated from a single outdoor unit. The system uses R32 refrigerant, supports a connected-capacity range of 50–150% of the outdoor unit’s nominal capacity, and is designed for operation in challenging outdoor conditions.

Key Features

Powerful Multi-Split Cooling– With a nominal 10.6 kW cooling capacity, the CHML-U36RK4-NG is designed to provide climate control across several rooms using one outdoor unit. Up to four compatible indoor units can be connected, allowing each room to have its own indoor climate-control zone. This makes the system a practical alternative to installing several separate outdoor units. The system can operate within a connected-capacity range of 50–150% of the outdoor unit’s nominal capacity, providing flexibility when selecting indoor units for different room sizes and requirements.

Efficient Heating for Cold Climates– The outdoor unit provides a nominal 12.0 kW heating capacity and is designed for cold-weather operation. The detailed manufacturer specification lists a heating operating range of −22°C to +24°C, making the CHML-U36RK4-NG suitable for regions where winter temperatures can fall well below freezing. This allows the multi-split system to be used not only for summer cooling but also as a supplementary heating solution during the cold season.

Inverter Technology– The CHML-U36RK4-NG uses inverter technology to continuously adjust compressor operation according to the current demand from the connected indoor units.

Key benefits include:

• Stable temperature maintenance
• Efficient part-load operation
• Reduced unnecessary compressor cycling
• Smooth capacity adjustment
• Lower mechanical stress
• Improved comfort

Cooper&Hunter’s Stable Frequency Control technology allows smooth compressor operation at ultra-low frequencies down to 15 Hz.

Noise Analysis Technology– The outdoor unit incorporates Noise Analysis Technology, developed to optimize the operating characteristics of the system and reduce unnecessary noise. The manufacturer’s specified outdoor sound level is approximately 58 dB(A). Because this is a high-capacity outdoor unit, professional installation and appropriate placement are recommended, particularly in residential areas.

R32 Refrigerant–  The CHML-U36RK4-NG uses R32 refrigerant, a modern refrigerant used in current-generation air-conditioning systems.

The manufacturer specifies:

• Factory refrigerant charge: 2.40 kg
• Additional charge: 20 g/m
• Standard pipe length without additional refrigerant: 30 m

Any additional refrigerant charge should be calculated according to the actual installed piping length and the manufacturer’s installation requirements.

 Flexible Installation– The CHML-U36RK4-NG provides considerable flexibility for multi-room installations.

This makes the system suitable for multi-level apartments, private houses and commercial spaces where the indoor units may be located at different distances from the outdoor unit.

One Outdoor Unit — Up to Four Indoor Units– One of the main advantages of the CHML-U36RK4-NG is the ability to connect 2–4 indoor units.

This configuration can help:

• Reduce the number of outdoor units on the building facade
• Provide independent temperature control in different rooms
• Simplify the overall appearance of the installation
• Save external installation space
• Create a customized climate-control system for different room sizes

Compatible indoor units should always be selected according to Cooper&Hunter’s approved combination tables. The manufacturer publishes numerous permitted combinations for the CHML-U36RK4-NG.

Intelligent Defrosting– The system uses a new-generation Intelligent Preheating automatic frost-protection system. Unlike conventional timer-based defrosting, the system initiates the defrost cycle when it is actually required. This helps reduce unnecessary defrost cycles and associated energy losses during winter operation.

Reliable Operation

The CHML-U36RK4-NG incorporates several technologies designed to maintain stable operation in demanding conditions:

• Stable Frequency Control
• Intelligent Preheating
• Automatic defrost
• Anti-icing protection
• Multi-speed outdoor fan
• Auto Restart
• Self-Diagnosis
• Voltage protection
• Blue Fin anti-corrosion protection

The manufacturer also specifies safe system start-up within a 96–260 V voltage range.

Wide Temperature Range–  According to the detailed manufacturer specification, the unit can operate within:

Cooling: −15°C to +43°C
Heating: −22°C to +24°C

Cooper&Hunter additionally describes the Nordic Multi Light R32 NG platform as being designed for efficient operation at temperatures down to −20°C for heating and up to +48°C for cooling under the series’ stated operating conditions.

Recommended Application– The CHML-U36RK4-NG is particularly suitable for:

• Large apartments
• Private houses
• Multi-room residential properties
• Offices
• Small commercial buildings
• Studios and multi-zone premises
• Properties where multiple outdoor units are undesirable

The actual conditioned area depends on the combination of indoor units, building insulation, ceiling height, glazing, solar exposure and internal heat loads. Therefore, the outdoor unit’s 10.6 kW capacity should not be converted directly into a guaranteed floor area without a proper heat-load calculation.

 Important Installation Information

This product is an outdoor unit only and cannot operate as a standalone air conditioner. A complete system requires compatible indoor units and professional installation.

Before ordering, verify:

1. The selected indoor units are compatible with CHML-U36RK4-NG.
2. The combined indoor-unit capacity falls within the manufacturer’s permitted range.
3. Total refrigerant pipe length does not exceed 70 m.
4. The maximum distance to an individual indoor unit does not exceed 20 m.
5. Height difference does not exceed 15 m.
6. Additional R32 refrigerant is calculated correctly when the piping exceeds the standard 30 m.
7. Electrical and installation requirements are met.

Specification	Value
Model	CHML-U36RK4-NG
Series	Nordic Multi Light R32 NG
Type	Multi-Split Inverter Outdoor Unit
Compatible Indoor Units	2–4
Cooling Capacity	10.60 kW
Heating Capacity	12.00 kW
System Capacity Range	50–150% of nominal outdoor-unit capacity
Energy Efficiency Class	A
Airflow Rate	3,800 m³/h
Outdoor Unit Sound Level	58 dB(A)
Refrigerant	R32
Factory Refrigerant Charge	2.40 kg
Additional Refrigerant	20 g/m
Standard Pipe Length Without Additional Charge	30 m
Power Supply	220–240 V / 50 Hz / 1 Phase
Cooling Operating Range	−15°C to +43°C
Heating Operating Range	−22°C to +24°C
Maximum Total Pipe Length	70 m
Maximum Distance to One Indoor Unit	20 m
Maximum Height Difference	15 m
Outdoor Unit Dimensions (W × D × H)	1020 × 427 × 826 mm
Outdoor Unit Net / Gross Weight	72 / 79 kg
Distance Between Mounting Points	570 mm