Installation of a Hitachi airHome 600 wall-mounted heat pump in Saint-Bruno-de-Montarville on Montreal’s South Shore

Commissioning in which performance was measured, not simply assumed

The photograph taken at the end of this wall-mounted heat pump installation in Saint-Bruno shows an essential step in our work at AirGreen: checking the unit’s actual performance after it has been started.

In front of the Hitachi airHome 600 indoor unit, our technician uses an infrared thermometer. The display shows a reading of approximately 5.3°C, with a maximum recorded value of around 5.4°C. This surface measurement, taken in the cooled area near the air outlet, quickly confirms that heat exchange has begun properly and that the unit is producing significant cooling.

However, this data must be interpreted correctly. An infrared thermometer does not directly measure the temperature of moving air: it measures the temperature of the targeted surface. For a complete analysis, we can also use a probe placed in the airflow and compare the return-air temperature with the supply-air temperature.

This technical distinction is important. A cold reading at the outlet is a useful indicator, but a professional HVAC commissioning is based on a series of checks, not a single number.

What the photo reveals about the job site

The Hitachi unit is installed neatly against a light-colored wall, beneath a section of ceiling or wall in a dark blue shade. Its louver is open and the fan is running at the time of the inspection. No loose cables or exposed connections are visible in the photographed area.

The close-up primarily highlights what happens after installation:

• starting the heat pump;
• confirmation of communication between the units;
• activation of cooling mode;
• stabilization of the Inverter compressor;
• checking cooling production;
• observing the air direction louver;
• listening for operating noises;
• confirmation of the unit’s overall operation.

An installation may appear flawless yet still have a hidden issue: an imperfect refrigerant connection, inadequate drainage, a communication error, an incorrect setting, or insufficient airflow. That is precisely why we check the unit while it is running.

Why a 5.3°C reading should not be presented as the room temperature

The number shown on the thermometer could easily be misinterpreted. It obviously does not mean that the room has been cooled to 5.3 °C. Rather, it represents the temperature of the surface targeted by the infrared beam, probably in the area immediately exposed to the cold airstream.

Several factors influence an infrared reading:

• the distance between the measuring device and the surface;
• the viewing angle;
• the material being measured;
• surface reflectivity;
• the actual diameter of the measured area;
• fan speed;
• the room’s temperature and humidity;
• the time elapsed since the heat pump was started.

We therefore use this measurement as a quick validation tool. When circumstances require it, we supplement the analysis with instruments suited to measuring air temperature, refrigerant pressures, electrical current, or airflow.

The temperature difference between return air and supply air

To evaluate cooling performance, one of the most useful checks is to compare:

1. the temperature of the air drawn in through the top of the unit;
2. the temperature of the air expelled through the lower louver.

The difference obtained depends on indoor conditions, humidity level, fan speed, and compressor modulation. An Inverter heat pump does not always operate at maximum capacity. It gradually adjusts its output according to demand.

A measurement must therefore be interpreted in context. The goal is not to obtain the lowest possible figure, but to confirm stable, consistent, and safe operation.

A vacuum that protects the compressor over the long term

Before starting a Hitachi airHome 600 heat pump, the refrigeration circuit must be prepared correctly. The copper pipes installed between the indoor and outdoor units initially contain air and moisture.

These contaminants must be removed through proper evacuation. An installation where this step is shortened may operate at first, but later develop:

• oil degradation;
• a chemical reaction with the refrigerant;
• internal corrosion;
• restrictions in the circuit;
• a loss of capacity;
• higher electricity consumption;
• a reduction in the compressor’s service life.

At AirGreen, speed of execution must never replace a proper refrigeration procedure. A heat pump intended to heat and cool a home for many years deserves a complete commissioning.

The connections required by the airHome 600 range

The series includes several capacities, and the piping dimensions are not identical for all models.

The liquid connection is generally 1/4 po, while the gas line varies depending on the combination:

• 3/8 po for certain smaller capacities;
• 1/2 po for certain intermediate capacities;
• 5/8 po for the largest configuration.

Using the correct diameters contributes to oil return, pressure control, and the equipment’s actual capacity. We always check the specific models of the indoor and outdoor units rather than relying solely on their appearance.

Drainage: an essential check for air conditioning

When the airHome 600 cools the room, the moisture in the air condenses on the indoor coil. This water falls into a pan and must then be discharged through the drain hose.

Our inspection covers, among other things:

• the drain’s consistent slope;
• absence of any upward sections along the route;
• strength of the connections;
• flow at the outlet;
• absence of leaks beneath the unit;
• sealing around the wall penetration;
• drainage behavior while the fan is running.

A heat pump can produce cooling properly while still having a drainage problem. If it is not detected, the consequences may include stains on the wall, drywall damage, odors, or water running onto the floor.

Electrical verification before handing the system over to the owner

The airHome 600 models operate at a nominal voltage of 208–230 V, single-phase, 60 Hz. Depending on the capacity, the documentation indicates a minimum circuit ampacity between 12 and 20 A, as well as maximum overcurrent protection of 15 or 25 A.

The circuit breaker rating must never be chosen at random. It must correspond to the installed combination and the nameplate data.

We also check:

• grounding;
• tightness of the connections;
• outdoor disconnect switch;
• communication cable;
• conductor polarity;
• cable protection;
• voltage stability.

A heat pump starting up does not automatically prove that the electrical connection complies with requirements. Some errors only appear after several cycles or when the compressor increases its capacity.

Features of the Hitachi airHome 600 suited to Saint-Bruno’s climate

In Saint-Bruno-de-Montarville, heat pump needs are not limited to the few hottest days in July. The unit must also manage summer humidity, fluctuating fall temperatures, and heating during a large part of the winter.

The Hitachi airHome 600 is an Inverter wall-mounted heat pump offered in nominal cooling capacities ranging from 9,000 to 22,000 BTU/h, with a commercial range covering the 9,000 to 24,000 BTU/h category. The various combinations can achieve up to 23.0 SEER2 and up to 9.2 HSPF2 for climate region 5. The product line uses R32 refrigerant, includes a Wi-Fi adapter, and is ENERGY STAR certified in the combinations presented by Hitachi.

Inverter technology: modulating instead of operating solely through stopping and starting

An Inverter compressor can adjust its speed according to the room’s needs. After a significant demand, the unit increases its output. As the temperature approaches the setpoint, it can gradually reduce its capacity.

This modulation provides:

• a more stable indoor temperature;
• fewer abrupt fluctuations;
• generally quieter operation;
• better consumption management;
• more consistent dehumidification;
• fewer full-load starts.

Proper sizing nevertheless remains essential. Inverter technology offers great flexibility, but it cannot completely compensate for a unit that is severely oversized or insufficient for the building’s load.

How we select capacity in Saint-Bruno

The photo does not make it possible to identify the installed unit’s BTU rating with certainty. We therefore avoid making up this information.

To choose a capacity, we consider, among other factors:

• the area actually served;
• the number of floors;
• ceiling height;
• the amount of glazing;
• window orientation;
• wall and attic insulation;
• the building’s airtightness;
• sun exposure;
• the layout of the rooms;
• the presence of another heating system;
• occupants’ habits.

An oversized heat pump

An oversized unit can cool the area near the appliance very quickly. It then reduces its output before the air in more distant rooms has mixed sufficiently.

It may also operate for periods that are too short to remove humidity effectively, especially on hot but moderately sunny days.

An undersized heat pump

An undersized unit may operate for long periods at high capacity during heat waves or cold spells. It may have difficulty maintaining the setpoint, particularly when doors are closed or airflow is limited.

Continuous heating down to -25 °C

The Hitachi airHome 600 is designed to maintain heating when the outdoor temperature drops to approximately -25 °C. The manufacturer also advertises 100% capacity at -15 °C for the series, depending on the models and specified conditions.

The minimum operating temperature must be distinguished from the capacity actually available. At -25 °C, the various combinations retain an advertised maximum capacity ranging approximately from 7,200 to 15,000 BTU/h.

In a home in Saint-Bruno, the existing heating system can therefore remain useful as a supplemental heat source during periods of extreme cold. A wall-mounted heat pump can considerably reduce the use of electric baseboard heaters or another system, without necessarily replacing every heating appliance in every room.

Adaptive defrost and heating element in the outdoor pan

In heating mode, the outdoor coil becomes cold enough for frost to accumulate. The system must periodically run a defrost cycle.

The airHome 600 includes adaptive defrost technology as well as a heating element in the outdoor condensate pan. These features facilitate the drainage of water from defrosting and reduce the risk of ice buildup in the unit.

However, the outdoor installation must provide:

• sufficient height above the snow;
• clearance for air intake and exhaust;
• safe water drainage;
• an appropriate distance from walls and obstacles;
• access for maintenance;
• protection against ice falling from the roof.

FrostWash 3.0: a coil self-cleaning cycle

FrostWash 3.0 technology operates in three stages.

Heating

The coil is heated to help loosen certain greasy particles.

Freezing

The coil is then cooled to approximately -15 °C, trapping some of the dust and contaminants in the ice.

Melting

The ice melts and carries the residue into the drain pan.

This feature can limit buildup on the coil between cleanings. However, it does not replace complete HVAC maintenance. The tangential fan, filters, louvers, and drain pan can accumulate contaminants that may eventually require manual cleaning.

PM2.5 activated carbon filter

The unit includes a stainless steel prefilter as well as an activated carbon purification filter designed for fine PM2.5 particles.

This system can help reduce certain particles and odors in the air recirculated by the unit. However, it does not replace:

• an air exchanger;
• a kitchen range hood;
• a bathroom fan;
• central filtration;
• a correction of a humidity problem;
• the removal of a source of mold.

The heat pump primarily treats the air in the area where it is installed. A home's air quality depends on an overall strategy for ventilation, filtration, and humidity control.

Mold protection

The mold protection function can circulate air through the internal components and heat the coil to reduce residual moisture.

This feature is preventive. It can help limit conditions that promote odors, but it does not remove contamination that has already developed in a neglected unit.

Wi-Fi control with airCloud Go

The Wi-Fi adapter is included in the combinations presented by Hitachi. The airCloud Go app notably allows users to:

• to change the setpoint remotely;
• to create a weekly schedule;
• to view an estimated consumption figure;
• to monitor an energy budget;
• to use certain voice commands;
• to automate operation according to habits.

This feature is convenient for homeowners who want to lower the temperature when they leave home and restore comfort before they return.

Smart Eco and SleepSense

The motion sensor associated with Smart Eco can detect when the room is unoccupied. After a period with no one present, the heat pump adjusts its operation to limit unnecessary energy consumption.

The SleepSense function gradually adjusts the temperature during sleep. It is designed to prevent uncomfortable fluctuations while reducing excessive demands on the compressor.

Quiet operation

Depending on the capacity and fan speed, the indoor noise level varies. Hitachi indicates that the level can drop to around 27 dB(A) for a specific 12,000 BTU/h combination in silent mode.

To preserve this benefit, the installation must be stable. A poorly secured plate, a pipe in contact with the structure, or an improperly fitted exterior trim can transmit vibrations, even if the unit itself is operating normally.

The mistakes we avoid during a wall-mounted installation

Several defects can reduce the efficiency of an excellent heat pump:

• select the capacity based solely on the number of square feet;
• install the unit too close to the ceiling;
• obstruct the upper air return;
• neglect the drain slope;
• crush the pipe insulation;
• use the wrong copper diameters;
• shorten the vacuuming process;
• install the outdoor unit too close to the ground;
• choose a circuit breaker without checking the nameplate;
• leave the job site without testing the heating and air conditioning;
• interpret an infrared reading as an exact air temperature.

The 5.3°C measurement visible in the photo thus takes on its full meaning: it is part of a broader procedure intended to confirm the final result.

Grants and eligibility of the installed combination

The airHome 600 series combinations presented in Hitachi documentation are ENERGY STAR certified and are listed as eligible for most provincial heat pump incentives.

Actual eligibility must always be confirmed based on several elements:

• exact indoor unit model;
• exact outdoor unit model;
• AHRI number;
• recognized low-temperature capacity;
• type of residence;
• main heating system;
• program criteria at the time of application;
• invoice and installation documents.

The commercial name “Hitachi airHome 600” alone is not enough to guarantee financial assistance or a specific amount.

An installation completed with concrete proof

This Hitachi airHome 600 wall-mounted heat pump installation in Saint-Bruno clearly reflects our approach at AirGreen. The unit is installed, the louvers are working, and the system produces cool air, but we still take the time to perform measurements.

The infrared reading visible in the photo is not used as a flashy selling point. It is one technical indicator among several others: drainage, communication, power supply, noise, air distribution, connections, and operating stability.

We apply this level of rigor to our wall-mounted heat pump installations in Saint-Bruno-de-Montarville, Boucherville, Saint-Basile-le-Grand, Longueuil, Brossard, Montréal, Laval, as well as throughout the South Shore and the North Shore.

A properly chosen heat pump must be properly installed. A properly installed heat pump must then be inspected before being handed over to its owner.