LG R32 Central Heat Pump | 4 Tons - 48,000 BTU

A 4-tonne power plant designed for the realities of Greater Montreal

In Greater Montreal, a 4-tonne (48,000 BTU) central heat pump is not a "standard" choice: it is often a key decision for a home's energy efficiency and everyday comfort. It is typically found in single-family homes, cottages, large renovated bungalows, some converted duplexes, and small apartment buildings where a ductwork system is already in place—or being upgraded.

What makes this type of project particularly interesting is that the nominal power is only a starting point. What really matters is the machine's ability to maintain stable comfort, manage humidity effectively, integrate properly into the air distribution system, and remain predictable when the weather changes rapidly (which often happens between Montreal , Laval , Longueuil , the North Shore and the South Shore ).

The LG R32 Central Heat Pump | 4 Tonnes - 48,000 BTU is based on a clearly identified outdoor/indoor combination:

• Outdoor unit: KUSXB481A

• Indoor unit: KNSLB481A

• AHRI Reference: 215588580

• Certification: ENERGY STAR® (including the Cold Climate designation)

It operates on R-32 refrigerant and offers an architecture designed for modern residential use: an indoor unit of the air handler type, multi-configuration, which facilitates adaptation to the mechanical constraints of the building.

The R-32: what it actually changes for a homeowner

For a homeowner, refrigerant is more than just a label. The key is keeping pace with the evolution of residential systems: a more modern refrigerant generally comes with more stringent handling and testing requirements. At AirGreen, this translates into strict work procedures: pipe protection, thorough leak checks, rigorous vacuuming, and final checks designed to maintain performance and reliability.

Why a central unit: uniform comfort and control, without compromise “room by room”

A well-designed central HVAC system allows you to achieve:

• A more consistent temperature between the basement, the ground floor and the upper floor

• A more consistent level of comfort in the more remote rooms (back bedrooms, basement office, rooms above the garage)

• Improved filtration capacity depending on the type of filter chosen and the needs of the home

• More consistent humidity management in air conditioning mode

These are very concrete advantages for homes where occupancy has changed: teleworking, bedrooms converted into offices, finished basements, or families who use all the rooms in the house more.

Actual heating capacity: the most important factor in the decision

In our climate, a central heat pump is often evaluated on its ability to remain effective for heating when the outside temperature drops significantly. A quality 4-tonne unit, properly installed, can cover a large portion of the heating needs of many homes, while also improving overall comfort.

Important: Actual performance depends as much on the building as on the equipment. Two houses of comparable size can have very different needs: insulation, windows, air infiltration, wind orientation, humidity levels, and especially the condition of the ductwork. This is precisely why we emphasize a methodical approach before recommending a system.

Efficiency: understanding what numbers mean in a real home

The advertised efficiency values ​​(SEER2, EER2, HSPF2) are useful, but they don't "guarantee" savings on their own. In practice, what makes the difference is the system's ability to operate within its optimal range.

• A suitable airflow, neither stifled nor excessive

• A balanced flow between rooms

• A clean, airtight conduit network adapted to the power

• Settings and a control strategy consistent with the household's habits

In many projects, the greatest improvement in comfort comes from an overlooked detail: insufficient air return, an improperly sized grille, a duct crushed during renovations, or a filter that's too restrictive for the fan. The unit itself may be excellent, but if the air doesn't circulate properly, it will have to compensate, and comfort will suffer.

Airflow and acoustic comfort: the “real” difference between a pleasant air conditioning unit and a tiring one

The noise perceived in a house equipped with a central air conditioning system rarely comes from the unit itself. It most often comes from the air velocity in the ducts, grilles that are too small, a poorly placed return air vent, or vibrations transmitted through unsuitable supports.

That is why, in the projects for Montreal , Laval and Longueuil , we pay particular attention to:

• Selection and adjustment of the grilles (supply and return)

• Reducing whistling noises (air velocity, transitions, ducts)

• Vibration management (supports, anchors, clearances)

• Intelligent positioning of the outdoor unit (distance from rooms, windows, terraces)

A power plant can become "invisible" in everyday life if it is well integrated. This is a realistic goal, but it requires a disciplined installation.

Installation in Montreal, Laval, Longueuil: our AirGreen method for a 4-tonne truck

Installing a 48,000 BTU central heat pump requires a structured approach. A 4-ton unit doesn't tolerate shortcuts: the ductwork, electrical supply, drainage, and cooling capacity must all be up to standard.

1) First and foremost: validate the building, not just the surface area

The most frequent requests we receive in Greater Montreal are very specific:

• “The basement is always colder than the upper floor.”

• “The room above the garage is impossible to stabilize.”

• “In summer, it’s humid even when it’s cool.”

• “The old system heats up, but the bill is too high.”

• “Some parts are noisy as soon as the blower starts.”

To answer correctly, we don't just look at the size of the house. We also check:

• Attic insulation, thermal bridges, air infiltration

• Condition of windows and doors, balance of floors

• Actual use of the rooms (office, gym, daycare, etc.)

• Mechanical constraints: access to the mechanical room, height, clearances

• Opportunities for improving the conduit network

This is a step that avoids costly mistakes: a machine that is too large can cycle too often (unstable comfort, less effective humidity control), while a machine that is too small will force a backup source sooner.

2) The conduit network: the place where projects gain or lose their value

In areas like Ahuntsic , Villeray , Rosemont , Saint-Laurent , Chomedey , Duvernay , Brossard or Saint-Hubert , one often sees networks of conduits from different eras:

• older metal pipes with leaking joints

• modifications made during renovations (walls moved, ceilings finished)

• Insufficient air return, especially on the second floor

• poorly positioned grilles (airflow "pushing" towards a door instead of circulating)

On a 4-ton truck, a faulty pipe quickly results in:

• areas that are too hot/too cold

• noise and drafts

• higher than expected fuel consumption

• accelerated wear of the system

Our approach is simple: if the network has limitations, we state them clearly and propose appropriate solutions. Sometimes, a small improvement (added air return, a resized grid, a removed restriction) transforms the experience.

3) Power supply: ensuring performance and reliability

A centralized system of this capacity requires rigorous electrical validation: voltage, panel capacity, circuit breaker, wire gauge, and compliance. It's not flashy, but it's one of the main reasons for avoidable service calls when it's neglected.

In a well-prepared project, the electrical installation is:

• correctly sized

• clean and safe

• Designed to last, without unexpected triggering

• in accordance with applicable requirements

4) Piping, insulation, drainage: the details that protect your investment

A central heat pump is a refrigeration system. The quality of the connections, the insulation of the piping, and the management of drainage are essential.

At AirGreen, our standard aims to avoid the classic causes of problems:

• moisture infiltration into the line during installation

• Insufficient insulation leading to condensation

• Poorly designed drainage leading to leaks or odors

• Vacuuming too quickly or incompletely

• Leak tests treated as a formality

In a home, poorly designed drainage can damage ceilings and walls, especially when the unit is in the basement with a longer condensate path. Our goal is for the homeowner to never have to think about drainage; it simply needs to work.

5) The location of the outdoor unit: comfort, noise and maintenance in winter

In our winters, the outdoor location must take into account:

• snow and accumulation (clearance, protection, height)

• prevailing winds and air recirculation

• access for maintenance

• the proximity of the bedrooms and relaxation areas (terrace, patio)

A good location reduces perceived noise, facilitates maintenance, and contributes to more stable operation during challenging times.

6) A multi-configuration indoor unit: a major advantage in homes here

An adaptable indoor unit is a valuable asset in homes where mechanical space is limited: basements with low ceilings, narrow mechanical rooms, and existing ductwork. The goal is to integrate the system without compromising service access, filtration, drainage, or air circulation.

This point, often underestimated, is crucial: an inaccessible system is less well maintained, and a poorly maintained system loses efficiency.

Case study 1: Upstairs renovation and comfort in Laval

In Laval , in a renovated house where the upstairs was becoming uncomfortable in winter, the owner wanted "more power." The analysis showed that the problem stemmed primarily from a lack of air return upstairs and an unbalanced airflow.
The correction (added air return + rebalancing of the grilles) produced an immediate result: a more stable temperature upstairs and a significantly improved feeling of comfort, without having to push the machine into aggressive cycles.

This type of example illustrates a reality: on a power plant, air distribution is as important as the machine itself.

Case study 2: Summer humidity on the island of Montreal

In Montreal , in a house where the summer was "sticky" even with air conditioning, the cause was a combination of factors: cycles that were too short, flow that was too high at certain grilles, and a control that did not promote effective dehumidification.
Once the settings were corrected and the balance adjusted, the comfort improved: the temperature seemed the same, but the air was drier, more stable, and the house much more pleasant.

The lesson: humidity is often the invisible factor that influences the perception of comfort.

Case study 3: Replacing an aging system on the South Shore

On the South Shore , in a project to replace an old central heat pump, the client's priority was reliability and stability in heating. The ductwork was adequate, but some sections had leaks and losses.
After addressing the most problematic issues (sealing, air return, balancing), the new system was able to operate more consistently. Comfort improved both through the modernization of the equipment and the optimization of the airflow.

Useful options: when they make a real difference

Some options and accessories are useful, but only when they meet a real need:

• Wi-Fi control : convenient for homeowners who are often away or for monitoring the house remotely

• Auxiliary heating : useful in houses with high exposure, or when the building envelope requires a heat reserve for extreme conditions

• Mechanical adaptations : necessary when the configuration of the ducts and the mechanical room requires a specific solution

Our approach is consistent: we recommend what improves the final result, not what increases the bill without concrete benefit.

Common mistakes to avoid (and that we often correct)

1. Oversizing without analyzing the ducts : bigger is not always more comfortable.

2. Neglecting the return air system : without return air, the air does not circulate, and the house becomes “unbalanced”.

3. Forgetting about the sealing of the ducts : leaks ruin efficiency.

4. Underestimating humidity management : summer comfort depends as much on humidity as on temperature.

5. Ignoring HVAC maintenance : an ill-suited filter, a forgotten seasonal check, and efficiency drops.

Maintenance: what protects your comfort and your savings

A central heat pump performs best when it is properly maintained. Good maintenance generally includes:

• Inspection and replacement/maintenance of the filter according to the frequency of use

• Checking the cleanliness of the components and the drainage

• Control of operating parameters

• Visual inspection of accessible ducts and potential leaks

• Seasonal adjustments if the house has changed (renovations, occupancy, new rooms)

In real life, homes change: renovations, extensions, enclosed rooms, different furniture, teleworking. A central system benefits from intelligent monitoring, especially after a full first season.

Why choose AirGreen for this type of installation?

For a central HVAC system of this size, the difference lies in the method:

• Structured analysis of the building and ducts

• Rigorous and meticulous refrigeration installation

• Serious electrical validation

• Clean and logical integration in the mechanical room

• Adjustments and balancing geared towards real comfort

• Reliable after-sales service: advice, adjustments, follow-up

We work every week in Montreal , Laval , Longueuil , on the North Shore and the South Shore . We know what local ductwork looks like, the typical mechanical constraints, and the expectations of homeowners: a comfortable, stable home, and a system that works without surprises.

Conclusion

If you're considering an LG R32 Central Heat Pump | 4 Tons - 48,000 BTU , the best approach is to start with your specific situation: ductwork, insulation, mechanical constraints, and lifestyle. Contact AirGreen for a clear estimate and recommendation tailored to your home in Montreal , Laval , Longueuil , on the North Shore , or the South Shore . We'll offer a comprehensive solution, professionally installed, providing consistent comfort year-round.