Installation of an ELIOS EMC wall-mounted heat pump in Godmanchester

A subtle, precise interior integration designed for efficient air distribution

In Godmanchester, we installed an ELIOS EMC wall-mounted heat pump in a room where interior aesthetics mattered just as much as heating and cooling performance. The project photo shows a white wall-mounted unit installed high on an open wall, just beneath an ornate ceiling molding. This placement preserves living space, avoids any obstruction in front of the unit, and maintains the room’s clean appearance.

The installation may seem simple when looking only at the completed indoor unit. However, the visible result represents the final stage of work that includes selecting the location, checking the wall structure, routing the refrigerant lines, managing the condensate drain, making the electrical connection, evacuating the circuit, and conducting complete operating tests.

For this project, our objective was clear: install a wall-mounted heat pump in Godmanchester capable of distributing air efficiently, without visually weighing down the room or compromising the access required for HVAC maintenance.

A high-mounted position that respects the room’s architecture

The indoor unit was placed in the upper part of the wall, beneath the decorative ceiling molding. This position offers several advantages when properly determined.

The cool air produced in summer can be projected forward and gradually distributed throughout the room. In heating mode, the louvers can be adjusted to direct warm air toward the occupied area rather than allowing it to accumulate unnecessarily near the ceiling. The front panel of the unit also remains accessible for filter cleaning and routine inspections.

However, we must maintain the clearances specified by the manufacturer. A unit placed too close to the ceiling may not receive enough air at the intake. A unit installed too low may blow directly onto occupants, occupy wall space unnecessarily, and reduce the air-distribution range.

In the photo, the unit is installed in an open area:

• No tall furniture blocks the air intake;
• No curtain risks being drawn against the unit;
• No decorative element interferes with the louvers;
• The air outlet remains unobstructed;
• Access to the front panel is preserved.

These details directly affect the heat pump's actual performance.

A visually discreet installation in a room with light-coloured finishes

The white casing of the ELIOS EMC blends into the wall and the room's mouldings. The integration is particularly successful when the lines and cables do not visually dominate the indoor installation.

Depending on the building's layout, the lines may exit directly behind the unit or follow a protected side route concealed by a finishing moulding. The exact path must be determined before drilling to avoid studs, electrical wires, plumbing pipes and structural elements.

In a home with decorative mouldings on the walls, we also take into account:

• unit alignment;
• the distance between the unit and architectural details;
• visibility from the room entrance;
• airflow direction;
• the possibility of carrying out the work without damaging the finishes.

A clean installation often depends on decisions made before the tools even come out.

Why the unit should not be chosen solely based on its width

The photograph shows the unit's positioning, but it is not enough to determine its nominal capacity with certainty. The ELIOS EMC range includes several sizes: 9,000, 12,000, 18,000, 24,000 and 33,000 BTU. Each capacity has its own dimensions, airflow rates, electrical requirements and pipe diameters.

The appropriate choice therefore depends on more than just the size of the available wall. We must consider:

• the actual area served;
• ceiling height;
• the level of insulation;
• the number and quality of windows;
• sun exposure;
• heat losses;
• air circulation to adjacent rooms;
• the use of the room;
• the presence of auxiliary heating.

An oversized heat pump can quickly reach the set temperature, but may operate in short cycles and dehumidify less effectively in summer. An undersized heat pump may run almost continuously during cold periods without maintaining the expected comfort level.

In Godmanchester, as elsewhere in Montérégie, sizing must take actual winter conditions into account, not just the cooling needs of July.

The ELIOS EMC series: heating down to -30 °C

The ELIOS EMC wall-mounted heat pump is designed for cold climates. The technical documentation indicates a heating operating range down to -30 °C, as well as a nominal heating capacity maintained at 100% at -15 °C thanks to Heat+ technology.

The series also uses a compressor with Inverter Drive technology, which modulates its operation according to demand rather than operating only at full capacity. This modulation helps reduce on-off cycles, stabilize indoor temperature, and adjust energy consumption to current needs.

Depending on the selected capacity, the range can achieve:

• up to 26.0 TRÉS2/SEER2;
• up to 10.1 CPSC2/HSPF2;
• ENERGY STAR 6.1 certification;
• ENERGY STAR Cold Climate certification;
• a 208-230 V, single-phase, 60 Hz power supply;
• heating and cooling operation down to -30 °C under the conditions specified by the manufacturer.

The series uses R454B refrigerant. Complete specifications, including capacities, dimensions, sound levels, maximum pipe lengths, and piping diameters, are provided in the ELIOS EMC brochure.

More stable comfort through compressor modulation

In a room like the one shown in the photo, comfort depends not only on the temperature displayed on the remote control. It also depends on how the unit modulates, distributes air, and responds to changes in load.

The Inverter compressor can slow down as the temperature approaches the setpoint. Instead of stopping completely and restarting frequently, it maintains output suited to demand. This approach generally helps to:

• limit temperature fluctuations;
• reduce abrupt starts;
• improve sound comfort;
• maintain more consistent air distribution;
• adapt energy consumption to actual conditions.

According to the manufacturer’s documentation, the EMC series uses compressor frequency control in fine 1% increments. This feature is particularly relevant during the shoulder seasons, when the building has little demand for heating or cooling.

An indoor unit designed for quiet operation

In a bedroom, office, or living room, indoor sound level is an important consideration. Depending on the model, EMC series units can reach approximately 20 dB(A) at their quietest setting.

The unit also includes a “Do Not Disturb” mode, which disables the display and audible alerts at night. The variable-speed fan offers several airflow settings, while turbo mode reaches the requested temperature more quickly.

However, the advertised low sound level does not eliminate the need for precise mechanical installation. A poorly secured wall bracket, a pipe in contact with the structure, or an inadequately supported drain can transmit vibrations. We therefore check the strength of the mounting, the unit’s alignment, and the routing of the pipes before commissioning.

Airflow direction: a detail that changes comfort

The choice of wall must take into account where occupants spend time. Installing a unit directly above a bed, sofa, or workstation can become uncomfortable if the air is constantly directed toward someone.

In this project, the unit was positioned on an unobstructed section of the wall. The goal is to project the air into the room rather than toward an immediately occupied area.

During commissioning, we check in particular:

1. the louvers opening fully;
2. the reach of the airflow;
3. the difference between heating and cooling modes;
4. the absence of vibration or unusual noise;
5. the response of the controls;
6. the supply air temperature;
7. condensate drainage.

We also explain to the owner how to adjust the louvers according to the season. In cooling mode, a more horizontal orientation generally promotes gradual distribution of cool air. In heating mode, a downward orientation helps bring warm air back toward the occupied area.

The technical steps behind such a clean indoor installation

Securing the wall plate

Before mounting the indoor unit, we must install a perfectly straight support plate. This plate must be securely fastened to the wall and suitable for the type of substrate.

A slightly tilted unit can affect condensate drainage and create a neglected appearance. We therefore check the level, anchor points, and space required for the connections before drilling the main passage.

In a room with clean architectural lines, even a small alignment difference relative to the moldings becomes noticeable. Positioning is therefore measured in relation to the ceiling, corners, and decorative elements.

Routing the refrigerant lines

The copper lines carry refrigerant between the indoor and outdoor units. Their diameter varies according to the capacity of the ELIOS EMC:

• 9,000 and 12,000 BTU: 1/4 in. and 3/8 in.;
• 18,000 BTU: 1/4 in. and 1/2 in.;
• 24,000 BTU: 3/8 in. and 5/8 in.;
• 33,000 BTU: 3/8 in. and 3/4 in..

The tubes must be bent without being crushed, properly insulated, and protected along their entire length. Flared connections must be made precisely and tightened according to the appropriate requirements.

Even a minor leak can reduce performance, trigger error codes, and eventually damage the compressor. That is why the circuit’s seal must be checked before releasing the refrigerant charge.

The condensate drain

In cooling mode, the indoor unit removes moisture from the air. This water must be discharged through a drain installed with a constant slope.

A poorly designed drain can cause:

• gurgling noises;
• water leaking inside;
• stains on the wall;
• moisture buildup;
• odors;
• damage to the materials.

When gravity drainage is possible, we favor a simple, continuous route. When it is not, a condensate pump may be necessary, but this adds a mechanical component that will eventually require maintenance.

Evacuation and Leak Testing

Evacuation is an essential step in any wall-mounted heat pump installation. It removes air and moisture from the lines before the refrigerant is circulated.

We do not rely solely on an arbitrary duration. The vacuum must be measured, and its stability must then be checked. A pressure rise may indicate a leak or the presence of moisture in the circuit.

This step directly affects compressor reliability and long-term performance. A visually successful installation must also be technically flawless inside the refrigeration circuit.

Two-Level Filtration and an Active-Cleaning Function

The ELIOS EMC features a two-filter system. The first helps capture dust, pollen, and pet hair. The second uses a carbon filter designed to absorb certain contaminants, including smoke and certain odors.

The active-cleaning function also helps limit the buildup of contaminants on the indoor coil. However, it is a supplement, not a replacement for maintenance.

We recommend removing and cleaning the filters regularly. The frequency depends on the environment, the presence of pets, the amount of dust, and the number of operating hours.

Reduced airflow can lead to:

• reduced capacity;
• longer operation;
• uneven distribution;
• increased noise;
• a risk of icing in cooling mode;
• a mistaken impression that the heat pump is too small.

The 8 °C Frost-Protection Mode

The EMC series offers a frost-protection mode that maintains an indoor temperature of approximately 8 °C. This feature can be useful in a second home, cottage, temporarily vacant dwelling, or little-used room.

It allows a minimum temperature to be maintained while reducing heating demand compared with a normal setpoint. For a property in Godmanchester, this option may be useful during an extended absence, provided that the entire building is adequately protected and air circulation is sufficient.

Auxiliary Heating and Optional Controls

The brochure mentions integrated auxiliary heating control, as well as possible compatibility with a 24 V interface for certain third-party thermostats. Wall-mounted controls and a touchscreen thermostat are also available as options, depending on the configuration.

These possibilities must be validated before installation. Do not assume that an existing thermostat can directly control a wall-mounted heat pump without a suitable interface.

We analyze the building’s heating logic, the presence of electric baseboards, and the owner’s habits to prevent two systems from unnecessarily heating the same area at the same time.

Mistakes to avoid after installation

To maintain the performance of the ELIOS EMC heat pump, certain simple practices are important.

Setting an extreme temperature to speed up heating

Setting the temperature to 30 °C does not necessarily heat the room faster. It mainly risks extending operation and causing overheating.

Frequently turning off the unit

An Inverter heat pump is designed to modulate. In many situations, it is preferable to maintain a stable setpoint rather than constantly turning the unit off and restarting it.

Completely closing the doors to adjacent rooms

A wall-mounted unit primarily heats the area where it is installed. Heat does not distribute effectively through several closed doors. To serve multiple rooms, airflow must be analyzed, and more than one unit may sometimes be required.

Neglecting the filters

Clogged filters reduce airflow and compromise comfort. Cleaning them is one of the simplest and most cost-effective maintenance tasks.

Constantly directing air toward occupants

The louvers must be adjusted to distribute air throughout the room. A direct draft can be uncomfortable even when the ambient temperature is correct.

An installation adapted to Godmanchester residences

This project demonstrates that a successful HVAC installation in Godmanchester can be both technical and discreet. The ELIOS EMC unit fits neatly into the room, maintains convenient access for maintenance, and distributes air from an unobstructed position.

At AirGreen, we also carry out wall-mounted heat pump installations in Montreal, Laval, Longueuil, on the North Shore and the South Shore. Each building has its own constraints: masonry walls, complex routes, low ceilings, narrow rooms, condos, older homes, or residences with multiple zones.

Our approach is to assess the entire project before installation:

• appropriate capacity;
• indoor unit location;
• outdoor unit location;
• pipe routing;
• drainage;
• power supply;
• noise;
• future access for maintenance;
• finish quality.

The visible result in the photo is a well-integrated wall-mounted unit. The desired technical result is broader: stable operation, consistent comfort, reliable drainage, and an installation designed to withstand Quebec conditions.