LG

LG Multi F MAX LGRED R32 Heat Pump | 5 Heads at 48,000 BTU | Montérégie

In stock
SKU: KUMXA481A
Provincial Subsidy (LogisVert): 4200 $ (Updated: November 26, 2025)
Model Number (External): KUMXA481A
AHRI: 215408636
ENERGY STAR®: Yes
ENERGY STAR® (Cold Climate): Yes / Yes
# ENERGY STAR ID: 3621305
Heating Capacity: -25 °C
Cooling Capacity: 48,000 BTU
Gas (Freon): R-32
WiFi: Included

SEER2 (Seasonal Air Conditioning Efficiency)

1 20.5 30

HSPF2 (Seasonal heating efficiency)

1 10.5 15

EER2 (Instantaneous efficiency in air conditioning)

1 13.1 20

COP at -8 °C (Heating energy efficiency)

1 2.09 3
Nominal Power: 48,000 BTU
Power at -8°C: 35000 BTU
Power at -15°C: 48000 BTU
Interior Dimensions (L x D x H): 32.94 x 7.56 x 12.13 in ***
Vertical flap control (Air direction): Auto ***
Horizontal flap control (Air direction): Auto ***
Sound Pressure Level (Indoor): 29 / 38 dB(A) ***(depending on the model chosen)***
Possible Model Number (Interior): KNUAK091A, KNUAK121A, NUAK181A, KNMAB071A, KNUAB091A, KNUAB121A, KNMAB151A, KNUAB181A, and KNMAB241A

CFM (Airflow) (12,000 BTU***)

1 459 700
External Dimensions (L x W x H): 37.41 x 15.34 x 54.34 in
Zones: 5 Areas
Maximum Zones: 8 Areas
Sound Pressure Level (Exterior): 56.0 dB(A)
Voltage: 220 V
MCA (Minimum Circuit Ampacity): 34 A
MOP (Maximum Overcurrent Protection): 40 A
Warranty (Compressor - Parts - Labor): 10-10-0 years
Additional Warranty: Possible

A multi-zone HVAC solution designed for demanding buildings in Quebec

In high-end residential projects, multi-unit buildings and commercial spaces in Montreal , Laval , Longueuil , the North Shore , the South Shore and the Montérégie region , the demand is clear: a multi-zone heat pump capable of offering independent room management, stable performance in winter heating and long-term mechanical reliability.
The LG Multi F MAX LGRED R32 – 48,000 BTU heat pump with 5 heads precisely meets these expectations, provided it is correctly selected, configured and installed , which is at the heart of AirGreen 's expertise.

This system is not a classic wall-mounted heat pump: it is a centralized multi-zone HVAC platform, designed to serve up to 8 indoor units , with a nominal capacity of 48,000 BTU in air conditioning and heating performance maintained down to -25°C , a fundamental criterion for the Quebec climate.


Technical architecture of the LG Multi F MAX LGRED R32 system

An outdoor unit designed for stability and longevity

The KUMXA481A outdoor unit is equipped with a variable-speed scroll compressor , using R-32 refrigerant, known for:

  • energy efficiency superior to several previous generations

  • a reduced refrigerant charge ,

  • a reduced environmental impact .

Unlike simplified residential multi-zone systems, the Multi F MAX is based on a professional distribution logic , with the option to integrate branch distribution units (BDUs) . This architecture allows for:

  • pressure stability in the refrigeration network,

  • better capacity distribution when multiple zones are operating simultaneously

  • a reduction in perceived temperature variations.

At AirGreen , we favour this type of system when the building configuration justifies a more advanced HVAC approach than standard multi-zone systems.


Actual capabilities and measured performance

Accuracy is key: some online marketing materials sometimes display unrealistic values. Here are the consistent and verified technical specifications for this model:

  • Rated cooling capacity : 48,000 BTU

  • Maximum heating capacity :

    • up to 56,500 BTU at +8 °C ,

    • approximately 45,200 BTU at -15°C ,

    • guaranteed operation down to -25 °C .

  • COP in heating (standard conditions) : approximately 3.6 to 3.8 , depending on the outside temperature.

  • External noise level : ~ 56 dB(A) , remarkable for a unit of this capacity.

These performance levels explain why this system is eligible for ENERGY STAR® Cold Climate programs and the LogisVert grant from Quebec, currently valued at $4,200 , subject to overall project compliance.


Flexibility of indoor units: a real multi-zone advantage

Wide selection of indoor heads

The LG Multi F MAX allows you to combine different types and capacities of indoor units, including:

  • 9000 BTU (KNUAB091A),

  • 12,000 BTU (KNUAB121A),

  • 14,300 BTU (KNMAB151A),

  • 18,000 BTU (KNUAB181A).

This flexibility is essential in real-world projects: a condo, a duplex, or a commercial space never has uniform thermal requirements.
At AirGreen , we systematically perform a room-by-room analysis , taking into account:

  • orientation,

  • glazed surfaces,

  • insulation,

  • actual uses of the premises.

This avoids common mistakes: unnecessary oversizing, acoustic discomfort or cycles that are too short.


Air distribution and actual comfort

The LG wall units associated with this system offer:

  • an automatic vertical and horizontal scan ,

  • modulated ventilation ,

  • interior noise levels as low as 27 to 29 dB(A) depending on the model and speed.

In several installations carried out by AirGreen in Boucherville and on the South Shore , this point was decisive for clients sensitive to noise, particularly in bedrooms or teleworking spaces.


HVAC Installation: Where Everything Really Happens

Refrigeration network and technical constraints

The Multi F MAX imposes strict rules:

  • Total piping length may exceed 450 ft .

  • Height differences between indoor and outdoor units can reach nearly 100 ft .

  • Precise sizing of liquid (3/8") and gas (3/4") pipes.

A sloppy installation inevitably leads to:

  • yield losses,

  • defrosting defects,

  • premature wear of the compressor.

This is precisely why AirGreen entrusts these projects only to certified refrigeration technicians , who are used to VRF / Multi F systems, and not to basic multi-zone installations.


AirGreen Experience Report – Montérégie

During a recent project in a multi-unit residential building in the Montérégie region , the client was hesitating between several multi-zone systems.
After analysis, the LG Multi F MAX was selected for:

  • stability in winter heating ,

  • the possibility of 5 independent zones with a single outdoor unit,

  • compatibility with municipal acoustic requirements.

Result after a full winter:

  • measured reduction in electricity consumption

  • consistent temperatures despite variations in exposure,

  • No complaints related to noise or defrosting.


Maintenance, reliability and long-term outlook

Recommended maintenance

A system of this scale requires:

  • Regular cleaning of the internal filters,

  • annual inspection of the refrigeration system,

  • checking operating parameters and defrosting.

AirGreen offers tailored HVAC maintenance programs specifically designed for complex multi-zone systems.


Guarantee and peace of mind

  • Compressor : 10 years

  • Parts : 10 years

  • Labor costs : variable, with the possibility of an AirGreen extended warranty

In large-scale projects, we systematically recommend an extended warranty , particularly in buildings with heavy use.


Why choose AirGreen for this type of heat pump?

Choosing the LG Multi F MAX LGRED R32 heat pump is a technical decision.
Choosing AirGreen means ensuring:

  • from an honest and realistic selection of the system,

  • of an HVAC installation compliant with LG and Quebec standards ,

  • comprehensive support , from design to maintenance,

  • with recognized expertise in Montreal, Laval, Longueuil, on the North Shore, the South Shore and in Montérégie .


Conclusion

The LG Multi F MAX LGRED R32 – 48,000 BTU, 5-head heat pump is a robust, scalable HVAC solution perfectly suited to complex projects in Quebec, provided it is properly designed and installed .

For a detailed quote , a personalized technical analysis or to validate eligibility for the LogisVert grant , contact AirGreen directly.
Our team will support you with the rigor and transparency that have built our reputation.