Installation of a Hitachi airHome 800 wall-mounted heat pump in Sainte-Catherine, on Montreal’s South Shore

An HVAC installation designed to integrate seamlessly into a modern kitchen

In Sainte-Catherine, on Montréal’s South Shore, we installed a Hitachi airHome 800 wall-mounted heat pump in a living space where choosing the location required as much technical precision as aesthetic care. The indoor unit had to provide effective air distribution while blending naturally into a streamlined kitchen with full-height cabinets, a pendant light, and a highly visible main wall.

In the photo taken during the final stages of the work, the Hitachi unit appears installed in the upper part of the wall, at a height that promotes air circulation throughout the room. Its white finish complements the surrounding light surfaces and minimizes its visual impact. The unit is positioned between the light fixture on the left and the kitchen cabinetry on the right, in an unobstructed area that allows the treated air to spread without being immediately blocked by a cabinet or architectural obstacle.

This installation clearly illustrates a reality frequently encountered in homes and condos in Sainte-Catherine, Longueuil, Brossard, Montréal and Laval: a wall-mounted heat pump should not simply be installed wherever space is available. Its location directly affects comfort, perceived noise levels, condensate drainage, accessibility for maintenance, and the system’s energy efficiency.

Why the indoor unit’s positioning was crucial

In this kitchen, several factors had to be considered before drilling the wall and securing the installation plate:

• the proximity of the ceiling;
• the presence of a tall cabinet on the right side;
• the space required to open the front panel;
• the circulation of air toward the occupied area;
• the passage of the refrigerant lines;
• the natural drainage of condensation water;
• future access to the filters and internal components.

We positioned the unit to maintain a functional clearance around its casing. A heat pump installed too close to a piece of furniture may experience air recirculation, create unnecessary turbulence, or become difficult to service. Conversely, a unit installed too low may blow cold air directly onto occupants and reduce its range in an open-concept area.

The result achieved in Sainte-Catherine allows the Hitachi airHome 800 to distribute air above the work surfaces without taking up usable kitchen space. The motorized louver then directs the airflow according to the selected mode and the occupants’ comfort preferences.

A discreet finish in a highly visible space

Wall-mounted units are often installed in a living room or hallway. In this project, the unit is fully visible from the kitchen and probably from part of the adjacent living area. The quality of the finish was therefore particularly important.

We paid particular attention to:

• the horizontal alignment of the unit;
• the consistent height relative to the ceiling;
• the stability of the wall plate;
• the cleanliness of the openings;
• the discreet routing of the connections;
• protection of the cabinets and countertop during the work;
• thorough cleaning of the area after the installation.

The ladder visible in the photo reflects the final inspection and adjustment phase. Before commissioning, we check the unit’s level, the panel closure, the deflectors’ freedom of movement, and the absence of abnormal vibration.

Drainage: an invisible detail that prevents many problems

In cooling mode, a wall-mounted heat pump naturally removes some of the moisture contained in the air. This moisture turns into water on the indoor coil, then flows into a drain pan and drain.

An inadequate slope, a pinched hose, or an improperly made connection can cause:

• water running down the wall;
• moisture buildup inside the unit;
• odors;
• damage to the paint or cabinets;
• premature wear of certain components.

In a fitted kitchen, protection against leaks is essential. We therefore plan the drain route before permanently securing the unit. Whenever the configuration allows, we favor continuous gravity drainage. If a condensate pump is necessary, its location and noise level must be carefully evaluated.

Refrigerant connections suited to the installed model

The Hitachi airHome 800 range is available in several capacities, from 9,000 to 24,000 BTU/h. The diameter of the refrigerant lines varies depending on the selected capacity. The 9,000 and 12,000 BTU models use 1/4 in. liquid-line and 3/8 in. gas-line connections, while higher capacities may require larger lines.

It is important to follow the manufacturer’s requirements exactly. Reusing old piping without checking its diameter, condition, cleanliness, or compatibility with the refrigerant can compromise compressor operation.

During our HVAC installations, we carry out the following tasks:

1. the precise cutting and flaring of the lines;
2. protecting the ends against moisture and contaminants;
3. tightening the connections according to the technical requirements;
4. a leak test;
5. a complete vacuum;
6. checking the pressure and operation after startup.

These steps are not visible once the work is complete, but they play a major role in the heat pump's long-term reliability.

The Hitachi airHome 800: comfort in extreme cold, purification, and smart control

The Hitachi airHome 800 is an Inverter wall-mounted heat pump designed to meet air-conditioning and heating needs in Quebec's climate. Its heating operating range extends down to -30 °C, while the manufacturer's documentation indicates that it maintains 100% heating capacity at -20 °C. Depending on the selected capacity, its seasonal efficiency can reach a TRÈS2 of 26.5 and a region 5 CPSC2 of 9.7.

These features make the series particularly appealing to homeowners in Sainte-Catherine and the South Shore who want to reduce their use of electric baseboard heaters or improve the comfort of an open-concept area.

Inverter technology and capacity modulation

Unlike a conventional system that operates only at full power before shutting off, Inverter technology gradually adjusts the compressor speed. When the desired temperature is nearly reached, the heat pump slows down instead of shutting off completely.

This modulation generally allows for:

• more stable temperature;
• fewer on-off cycles;
• quieter operation;
• better dehumidification in summer;
• electricity consumption better suited to actual demand;
• a reduction in sudden temperature fluctuations.

In a kitchen and living area, where heat can vary depending on cooking, sunlight, and the number of occupants, this adaptability significantly improves comfort.

A heat pump designed for Quebec heating

Cold-weather performance is an essential criterion when choosing a heat pump in Sainte-Catherine. A unit that performs efficiently at 8 °C does not necessarily guarantee good capacity when the temperature drops below -15 °C.

The Hitachi airHome 800 uses HeatForce technology and adaptive defrosting designed to maintain performance when frost forms on the outdoor unit. The technical specifications indicate a heating operating range of -30 °C to 24 °C.

However, the capacity actually required for a property must be determined based on several factors:

• the surface area of the area to be treated;
• the insulation;
• the number and type of windows;
• the building's orientation;
• ceiling height;
• the layout of the rooms;
• air leaks;
• the presence of other heating systems.

At AirGreen, we avoid choosing capacity based solely on square footage. An oversized heat pump may run excessively short cycles in cooling mode, while an undersized model may operate continuously without achieving the expected comfort during the coldest periods.

Quiet operation suited to living spaces

The 9,000 and 12,000 BTU models in the airHome 800 series can operate as quietly as 30 dB(A) in silent mode. This feature is particularly appreciated when the indoor unit is located in an open-concept kitchen, near a living room, or close to an area used in the evening.

The actual sound level nevertheless depends on the fan speed, the heating or cooling demand, and the room's resonance. A solid, perfectly level installation also helps prevent vibrations or rattling noises.

FrostWash 3.0 and Mold Guard 2.0

One of the distinctive features of the Hitachi airHome 800 is its set of self-cleaning functions.

FrostWash 3.0 technology uses a cycle involving heating, freezing, and thawing to detach contaminants from the indoor coil. According to Hitachi, this technology helps reduce the buildup of bacteria, mold, particles, and certain odors.

The Mold Guard 2.0 function monitors conditions inside the unit even when it is turned off. When conditions favorable to mold growth are detected, the system can heat the coil to dry it.

These technologies do not replace professional HVAC maintenance, but they can help keep the indoor heat exchanger cleaner between maintenance visits.

PM2.5 filtration and stainless-steel prefilter

The heat pump includes a PM2.5 activated carbon filter designed to capture small particles and help reduce certain odors and volatile organic compounds. It also has a washable stainless-steel prefilter.

To maintain adequate airflow, the owner should inspect and clean the filters regularly. In a kitchen, this precaution is even more important, since cooking vapors and fine grease particles can accumulate more quickly.

A clogged filter can cause:

• reduced airflow;
• reduced performance;
• increased energy consumption;
• a colder coil in cooling mode;
• overheating or excessive strain on the system;
• more fan noise.

Wi-Fi control with the airCloud Go app

The Wi-Fi interface is designed for concealed installation inside the unit. The airCloud Go app allows remote control of the heat pump and access to several functions, including:

• weekly scheduling;
• temperature adjustment;
• the Smart-Fence function;
• estimated consumption monitoring;
• activation of FrostWash;
• display of certain error codes;
• integration with Amazon Alexa and Google Home.

The Smart Eco function uses a motion sensor to detect when the room is unoccupied. After a period with no presence detected, the system can automatically reduce its consumption, then return to the initial setting when occupants return.

In a kitchen used intensively at certain times of day, this automation makes it possible to adapt operation to actual habits rather than constantly maintaining the same setting.

R32 refrigerant and installation requirements

The Hitachi airHome 800 operates with R32 refrigerant, which has a lower global warming potential than several refrigerants used in previous generations of heat pumps.

R32 nevertheless requires appropriate tools, procedures, and handling. Refrigeration work must be carried out by qualified technicians, with thorough evacuation and a complete leak check.

The electrical circuit must also be sized according to the exact capacity. The technical data sheet indicates a minimum circuit ampacity of 14 A for the 9,000 and 12,000 BTU models, and 20 A for the 18,000 and 24,000 BTU models. The maximum overcurrent protection also varies by model. Therefore, a circuit breaker must never be selected solely based on another heat pump with a similar capacity.

Commissioning and final checks

Once the installation in Sainte-Catherine is complete, commissioning includes several checks:

• startup in cooling and heating modes;
• remote control verification;
• checking communication between the units;
• confirmation of airflow;
• drainage inspection;
• check for noise or vibration;
• verification of supply air temperatures;
• explanation of the main functions to the homeowner;
• reminder of filter cleaning procedures;
• verification of the warranty registration requirements.

Hitachi documentation presents a standard warranty of seven years on the compressor and five years on parts. Extended coverage may be available for residential installations when registration requirements are met. The exact terms must always be confirmed at the time of purchase and installation.

Eligibility for heat pump rebates

The airHome 800 series may qualify for certain financial assistance programs, depending on the model, capacity, energy reference number, building type, and the rules in effect at the time of application.

Before including a subsidy amount in a quote, we verify in particular:

• the exact combination of the indoor and outdoor units;
• the recognized heating capacity;
• the applicable AHRI number or energy reference;
• the type of residence;
• the existing heating system;
• the program’s documentation requirements;
• the purchase and installation date.

A heat pump belonging to an eligible product line does not automatically guarantee that a specific configuration will qualify for financial assistance. This validation helps avoid unpleasant surprises after the work is completed.

Mistakes to avoid when installing a wall-mounted unit

The installation carried out in Sainte-Catherine serves as a reminder of several common mistakes:

Installing the unit too close to a cabinet

Insufficient clearance can impair air intake, complicate maintenance, and cause airflow recirculation.

Neglecting the drain slope

Even a slight reverse slope can cause water accumulation and intermittent leaks.

Choosing capacity based solely on floor area

Two homes of the same size may have very different heating and cooling loads.

Reusing lines without inspection

An old system may contain incompatible oil, moisture, contaminants, or improper connections.

Failing to register the warranty

Some extended protections require registration within a specific period after installation.

Never cleaning the filters

A heat pump equipped with self-cleaning features still requires regular filter maintenance and periodic professional inspection.

An installation adapted to properties in Sainte-Catherine and Greater Montreal

This Hitachi airHome 800 wall-mounted heat pump installation in Sainte-Catherine demonstrates our approach: selecting a logical location, protecting the existing layout, complying with refrigeration and electrical requirements, and then completing a full commissioning.

We carry out similar installations throughout Greater Montreal, including Montreal, Laval, Longueuil, the South Shore, and the North Shore. Each project is adapted to the building’s actual configuration rather than reproduced according to a one-size-fits-all method.

In this specific case, the unit is discreetly installed above an unobstructed kitchen wall, maintains good airflow reach, and remains accessible for cleaning. The result combines heating in cold weather, summer cooling, humidity management, smart features, and integrated cleaning technologies.