Installation of a Hitachi airHome 800 wall-mounted heat pump in Fabreville, Laval

Precision commissioning to confirm the system's actual performance

In Fabreville, in western Laval, we installed a Hitachi airHome 800 wall-mounted heat pump to provide the homeowner with a complete solution for heating, cooling, and humidity management. The project did not end when the indoor unit was mounted on the wall: a professional installation also requires structured commissioning, operational checks, and concrete confirmation that heat is being produced.

The photo taken during our service call shows one of these checks. A member of our team is using an infrared thermometer in front of the indoor unit's air outlet. The device displays a reading of approximately 34.8 °C, with a recorded maximum temperature of approximately 35.3 °C. This quick measurement allowed us to confirm that the heat pump was actually producing heat after startup.

However, it is important to understand what this reading represents. An infrared thermometer primarily measures the temperature of a targeted surface, not directly the temperature of moving air. In this case, the measurement therefore serves as a supplementary check of the internal surfaces and heated louvers. For a complete analysis, we also observe the unit's behavior, airflow, ambient temperature, stabilization time, and the absence of an error code.

This attention to detail is part of our approach for every HVAC installation in Laval, whether the project is located in Fabreville, Sainte-Dorothée, Chomedey, Vimont, or Duvernay.

Why commissioning is just as important as installation

A wall-mounted heat pump may appear to be operating normally as soon as its fan starts. However, several technical problems may remain invisible during the first few minutes:

• a slightly leaking refrigerant connection;
• an inadequate amount of air or refrigerant;
• unstable communication between the two units;
• an improperly positioned drain;
• vibration coming from the support;
• a motorized damper that does not move properly;
• an incorrect operating mode configuration;
• insufficient airflow caused by an obstruction.

At AirGreen, we do not limit ourselves to confirming that the unit turns on. We operate the system, observe its response, and verify that the installation meets the manufacturer's technical requirements.

In the Fabreville project, monitoring heat production was particularly relevant. The homeowner had chosen a heat pump designed for Quebec’s winter conditions and wanted to ensure that the system responded properly from the first use.

The technical steps completed before the temperature test

Before pointing the thermometer at the indoor unit, several steps had already been completed.

Mounting and leveling the indoor unit

The wall plate must be installed on a sufficiently solid and perfectly level structure. A unit that is slightly tilted in the wrong direction can interfere with condensate drainage in summer. It can also cause cracking noises, vibrations, or improper enclosure closure.

We check, in particular:

• the strength of the mounting;
• the clearance above the unit;
• the space required to open the front panel;
• filter accessibility;
• the reach of the airflow;
• the direction of the connections;
• the possibility of carrying out future HVAC maintenance.

Refrigeration circuit connection

The copper lines connect the indoor unit to the outdoor unit. Their diameter depends on the system’s exact capacity. The Hitachi airHome 800 range includes 9,000, 12,000, 18,000, and 24,000 BTU/h models. Smaller-capacity models generally use a 1/4 in. liquid line and a 3/8 in. gas line, while higher capacities require different sizes.

Each connection must be carefully prepared. An improper cut, uneven flaring, or overtightening can cause a leak. Conversely, an insufficiently tightened connection can gradually lose refrigerant and reduce heating performance.

Leak test and evacuation

Evacuation is not only used to “remove air.” It also eliminates moisture present in the piping. If water remains in the refrigeration circuit, it can react with the compressor oil, create contaminants, and affect the system’s durability.

We therefore use appropriate instruments to check for leaks and obtain a stable vacuum before releasing the refrigerant contained in the outdoor unit.

Drainage inspection

In air conditioning mode, the indoor unit produces condensate. The drain must therefore have a continuous slope and be protected against kinks or upward bends.

Poorly designed drainage can cause:

• a water leak on the wall;
• an accumulation in the pan;
• a musty odor;
• damage to the interior finish;
• a buildup of deposits in the pipe;
• a safety shutdown if a condensate pump is used.

Even though the photo shows a heating check, we inspect the drainage before considering the project complete.

What we observe during heating startup

An Inverter heat pump does not necessarily produce its maximum temperature within the first few seconds. The system gradually increases its operating level according to the difference between the room temperature and the setpoint.

During commissioning in Fabreville, we allowed the unit to stabilize before evaluating its behavior. We paid attention to several elements:

1. Indoor fan startup delay
   In heating mode, the unit may wait until the coil is sufficiently warm before blowing air to avoid a feeling of cold air.
2. Temperature progression
   The outlet should gradually warm up as the compressor increases its speed.
3. Airflow stability
   Irregular airflow may indicate an adjustment, an obstruction, or a ventilation problem.
4. Deflector movement
   The louvers must respond to the remote control and direct the air correctly.
5. Operating noise
   We check for the absence of abnormal vibration, rubbing, or resonance.
6. Communication with the outdoor unit
   No error code should appear while changing modes or setpoints.

The visible reading in the photo is therefore one of several checks. It documents a specific moment during commissioning, but our assessment never relies on a single measurement.

A well-positioned wall-mounted heat pump improves comfort

The choice of indoor unit location directly affects comfort. A unit installed too close to a ceiling, in an enclosed corner, or facing an obstruction may have difficulty distributing air evenly.

We look for a location that allows:

• unrestricted intake from above;
• easy access to the filters;
• air distribution across most of the area;
• a reasonable distance from occupants;
• a logical piping route;
• reliable drainage;
• a clean exterior finish.

When heating, warm air naturally tends to rise. The louver orientation therefore becomes important to project heat downward and encourage it to mix with the cooler air in the room. In cooling mode, the airflow can be directed more upward or horizontally to prevent a cold draft from hitting occupants directly.

Why the Hitachi airHome 800 is suitable for winters in Fabreville and Greater Montreal

The Hitachi airHome 800 is an Inverter wall-mounted heat pump designed to provide three main functions: air conditioning, cold-weather heating, and supplementary indoor air treatment.

The series offers a heating operating range down to -30 °C. Hitachi also indicates that the system can maintain 100% of its heating capacity at -20 °C, depending on the model and test conditions. Its efficiency can reach a TRÈS2 of 26.5 and a region 5 CPSC2 of 9.7 for certain capacities.

These figures vary from one capacity to another. It is therefore essential to compare the exact model, not just the series name.

A capacity that must be selected according to the home

The brochure presents four main nominal capacities:

• 9,000 BTU/h;
• 12,000 BTU/h;
• 18,000 BTU/h;
• 24,000 BTU/h.

The exact capacity of the photographed installation cannot be confirmed from the appearance of the indoor unit alone. Several models share a very similar casing. The choice must be validated using the model numbers shown on the nameplates, invoice, or technical file.

At AirGreen, we do not size a heat pump in Fabreville based solely on floor area. We also analyze:

• the level of insulation;
• the year of construction;
• the size and orientation of the windows;
• ceiling height;
• the number of floors;
• air infiltration;
• whether the rooms have an open or closed layout;
• solar heat gains;
• the existing heating system;
• the desired indoor temperature.

An oversized heat pump can quickly reach its setpoint and run shorter cycles, which reduces summer dehumidification. An undersized unit may run for long periods without covering heat losses during periods of extreme cold.

HeatForce technology and maintaining heating in cold weather

Hitachi’s HeatForce technology is designed to maintain high heating capacity as the outdoor temperature drops. The technical specifications indicate that the various models continue to produce heat down to -30 °C, although their maximum capacity gradually decreases at extreme temperatures.

For example, heating capacities at -30 °C vary by model. This information is often more useful than the nominal capacity advertised at a moderate outdoor temperature.

When a homeowner compares heat pumps, we recommend examining:

• the capacity at -8 °C;
• the capacity at -15 °C;
• the capacity at -20 °C;
• the remaining capacity at -25 °C or -30 °C;
• the coefficient of performance at low temperatures;
• the building's actual heating needs.

This analysis determines whether the heat pump can cover most of the heating needs or whether a backup system must remain available.

Adaptive defrost for damp and icy conditions

In winter, outdoor moisture can freeze on the outdoor unit's coil. The heat pump must then run a defrost cycle.

A poorly optimized defrost system can operate too often, temporarily reduce heating, and consume more energy. The airHome 800 uses an adaptive defrost system to adjust cycles to the observed conditions.

The outdoor unit's location remains crucial. We must allow for:

• sufficient clearance beneath the unit;
• space for defrost water to drain;
• adequate clearance from accumulated snow;
• unrestricted airflow;
• protection against falling ice or water from a roof;
• access for maintenance.

In Laval, blown snow and accumulations near the foundation can quickly block a unit installed too low. A wall bracket, raised base, or protective accessory may be recommended depending on the property.

A sound level suited to living areas

The 9,000 and 12,000 BTU indoor units can reach a minimum advertised sound level of 30 dB(A) in silent mode. Outdoor units have a higher sound level, which varies according to their capacity.

Perceived noise also depends on the installation. An outdoor unit mounted on a lightweight structure can transmit more vibrations than a unit installed on a stable, properly isolated base.

We therefore assess:

• the strength of the wall;
• the proximity of bedrooms;
• the distance from neighbors;
• potential resonance;
• the type of support;
• the presence of ducts, balconies, or reflective surfaces.

FrostWash 3.0: a coil self-cleaning cycle

The Hitachi airHome 800 features FrostWash 3.0 technology. The process first heats the coil, cools it until frost forms and traps contaminants, then melts this layer to flush away impurities.

According to Hitachi documentation, tests have observed a reduction in certain viruses, bacteria, molds, and odors on treated surfaces. These functions help limit buildup on the heat exchanger, but they do not replace filter cleaning or thorough maintenance when the unit becomes dirty.

Why maintenance is still necessary

Even a unit equipped with a self-cleaning cycle gradually accumulates:

• dust;
• fibers;
• greasy particles;
• residue from pets;
• deposits on the fan;
• contaminants in the drain pan.

During wall-mounted heat pump maintenance, we inspect the filters, coil, fan, drain pan, drain, and electrical components. A dirty fan can reduce airflow even when the coil appears relatively clean.

Mold Guard 2.0 against internal moisture

The Mold Guard 2.0 function monitors the unit’s internal conditions. When the unit detects a combination of temperature and humidity favorable to mold growth, it can heat the coil to dry it.

This function is particularly useful during humid periods, when the heat pump alternates between cooling and being off. After a cooling cycle, the coil remains wet. Controlled drying can therefore limit conditions favorable to odors.

PM2.5 filtration and stainless steel pre-filter

The airHome 800 includes a PM2.5 activated carbon filter and a stainless steel pre-filter. The carbon filter helps capture fine particles and reduce certain odors.

To maintain its efficiency, the homeowner must clean the pre-filter regularly. The frequency depends on several factors:

• presence of pets;
• renovation work;
• frequent kitchen use;
• proximity to a busy street;
• window-opening habits;
• number of occupants.

A clogged filter restricts airflow, increases noise, and can reduce the amount of heat or cooling distributed.

airCloud Go app and Wi-Fi control

The Wi-Fi interface is designed to be discreetly integrated into the indoor unit. The airCloud Go app notably allows users to:

• to adjust the temperature remotely;
• to schedule time periods;
• to use the Smart-Fence function;
• to track an estimated energy consumption;
• to activate certain cleaning functions;
• to view error codes;
• to integrate the heat pump with Alexa or Google Home.

For a Fabreville homeowner who leaves the house during the day, remote control makes it possible to lower the setpoint and restore comfort before returning.

Smart Eco and occupancy detection

The built-in motion sensor can detect when a room remains unoccupied. After a set period, the system automatically reduces its operation, then resumes the initial settings when occupants return.

This feature can be useful in a family area, but its effectiveness depends on the sensor's visibility. A unit installed facing a lightly used area may not interpret occupancy in the same way as a device oriented toward the main living space.

Positioning should therefore not be chosen solely to facilitate the routing of the pipes.

R32 refrigerant and environmental efficiency

The Hitachi airHome 800 uses R32 refrigerant. It has a lower global warming potential than the R410A used in many older systems.

However, its use requires appropriate procedures. Technicians must have compatible tools, follow safety rules, and perform a thorough vacuum evacuation.

A new R32 heat pump must never be connected to old piping without verifying:

• the diameters;
• the thickness of the pipes;
• their condition;
• their cleanliness;
• the presence of residual oil;
• their compliance with the manufacturer's requirements.

Electrical requirements by capacity

The 9,000 and 12,000 BTU models have a stated minimum circuit ampacity of 14 A, while the 18,000 and 24,000 BTU models indicate 20 A. The maximum overcurrent protection is 25 A for the two smaller models and 35 A for the two larger models.

These values must not be used alone to select the wiring or circuit breaker. The electrician must verify:

• the unit nameplate;
• the manufacturer's requirements;
• the circuit length;
• the conductor size;
• the type of installation;
• the electrical standards applicable in Quebec.

Unit warranty and registration

Hitachi documentation provides a standard warranty of seven years on the compressor and five years on parts. A ten-year extended warranty on the compressor and parts may be available for residential installations with a qualifying online registration. An enhanced option may also include extended labor coverage, subject to the applicable terms.

After installation, it is important to keep:

• itemized invoice;
• serial numbers;
• indoor and outdoor model numbers;
• commissioning date;
• proof of registration;
• documents related to a potential subsidy.

Potential eligibility for financial assistance

The airHome 800 line is presented as eligible for several provincial incentives. However, actual eligibility depends on the exact combination of equipment and the rules in effect when the application is submitted.

Before confirming financial assistance, we verify:

• the complete model number;
• the recognized heating capacity;
• the energy certification;
• the AHRI number or applicable reference;
• the type of residence;
• the available program;
• the purchase and installation date;
• the required documents.

The amount should never be estimated solely from the number of BTUs indicated in the unit's commercial name.

Mistakes this installation helps avoid

Relying solely on the temperature displayed on the remote control

The set temperature does not prove that the unit is producing heat properly. The system's actual response must be observed.

Using an infrared thermometer as the sole measurement

An infrared thermometer measures a surface, not the air directly. It is a supplementary tool, as shown in the photo of our work in Fabreville.

Choosing the capacity without analyzing heat loss

Floor area alone is not enough to size a heat pump intended for winter heating.

Installing the outdoor unit too close to the ground

Snow and ice can block the heat exchanger or hinder the drainage of defrost water.

Neglecting to register the warranty

A unit eligible for an extended warranty may lose this benefit if the required steps are not completed within the specified time limits.

Believing that FrostWash eliminates the need for all maintenance

Automatic functions reduce buildup on certain surfaces, but they do not always clean the turbine, filters, drain and entire casing.

A verified result before leaving the premises

This Hitachi airHome 800 wall-mounted heat pump installation in Fabreville illustrates our approach at AirGreen: we place just as much importance on commissioning as on installing the equipment.

The measurement visible in the photo confirms that the unit is producing heat, but above all, it reflects our commitment to verifying the work performed in a practical way. Before leaving the property, we make sure that the system responds to the controls, that air is distributed properly, that the connections are stable and that the owner understands the essential functions of their new heat pump.

We carry out this type of HVAC installation throughout Laval, as well as in Montréal, Longueuil, the North Shore and the South Shore, using a method adapted to each building, capacity and interior configuration.