Installation of an ELIOS R454B electric furnace in Saint-Antoine-sur-Richelieu, Montérégie

A central integration carried out in an extremely compact mechanical space

In Saint-Antoine-sur-Richelieu, our AirGreen team completed an installation of an ELIOS R454B electric furnace in a mechanical space where every centimeter had to be used precisely. The photo clearly shows the reality of the worksite: a vertical indoor unit integrated into a narrow closet, surrounded by existing ducts, wiring, refrigerant lines, and control components.

This type of project requires much more than simply replacing a unit. First, it is necessary to understand the logic of the existing network, verify airflow, maintain access to the service panels, and adapt the connections without creating unnecessary restrictions.

In this installation, the new ELIOS unit was positioned on a raised metal base. The cabinet is installed very close to the side wall, but front access remains possible. The panels were removed during the connection and commissioning phase, making it possible to see the indoor fan, electrical components, control connections, and the routing of the lines.

The final configuration also had to comply with the constraints of the adjacent corridor. The system is located in a passageway and storage area, requiring an organized, compact, and safe installation.

A photo taken during commissioning

The photograph does not show the installation fully closed up. It was taken during the work, while several panels remained open.

In particular, we can observe:

• the indoor unit's vertical cabinet;
• the central motor and fan;
• accessible electrical components;
• the large-diameter insulated refrigerant line;
• the copper liquid line;
• the indoor unit's service valves;
• the communication cables;
• the existing metal ducts above;
• a galvanized base beneath the unit;
• the temporarily dismantled panels nearby.

This phase is essential. Before replacing the panels, we must confirm that the system responds correctly to all commands and that the different sequences work as expected.

Commissioning generally includes tests in:

• ventilation;
• heat pump heating;
• auxiliary electric heating;
• air conditioning;
• defrosting;
• emergency mode;
• safety shutdown;
• communication with the thermostat.

Why choose an ELIOS electric furnace for this home?

A central electric furnace, or indoor heat pump unit, distributes air throughout the house through a duct network.

For a property in Saint-Antoine-sur-Richelieu that already has a forced-air system, this configuration makes it possible to modernize the heating and air conditioning without installing several wall-mounted units throughout the rooms.

The Central-Elios system operates with an outdoor heat pump using the refrigerant R454B. The indoor unit contains the fan, refrigerant coil, controls and, depending on the configuration, auxiliary electric heating elements.

The range is available in capacities from 24,000 to 60,000 BTU, depending on the selected indoor-outdoor combination. The units are designed for heating in cold climates and can operate down to -30 °C, according to the manufacturer’s data.

A restricted service area requiring complete planning

One of the main challenges of this project was the available space.

The system is located in a narrow opening between a finished wall and a storage area. Above the unit, the ducts and connections occupy almost all the available height.

A positioning error of just a few centimetres could have prevented:

• panel opening;
• motor removal;
• access to the electronic control board;
• heating element replacement;
• coil inspection;
• drain maintenance;
• the routing of the refrigerant lines;
• the proper closure of the cabinet.

We therefore had to plan the work sequence before permanently securing the unit.

For this type of project, the team often has to proceed as follows:

1. measuring the available opening;
2. confirming the cabinet’s width and depth;
3. checking the airflow direction;
4. preparing the base;
5. positioning the lines;
6. connecting the ducts;
7. installing the drainage;
8. making the electrical connections;
9. checking access to the panels;
10. performing operational tests.

The metal base: an unobtrusive but essential component

The furnace rests on a galvanized sheet-metal base made for this installation.

This base serves several functions:

• it places the unit at the correct height;
• it facilitates alignment with the existing ductwork;
• it stabilizes the cabinet;
• it protects the lower part of the appliance;
• it can serve as a transition to the return air;
• it helps maintain clearance from the floor.

The tiled floor makes it easier to maintain the area, but the unit should still not be placed directly in an area where a water leak could accumulate.

The base must be rigid and properly sealed. An air leak at this point can draw in unfiltered air or reduce the amount of air circulating through the ductwork.

A vertical installation suited to the existing ductwork

The ELIOS unit is installed in a vertical position. This configuration is common in basements and mechanical closets when the ductwork rises toward the upper floors.

Return air generally enters through the lower or side section of the system, passes through the filter, flows over the coil and fan, and is then pushed into the supply ductwork.

The exact direction of airflow must be confirmed according to the cabinet configuration. An error at this stage can make the system ineffective or prevent it from operating normally.

We therefore check:

• the coil orientation;
• the position of the fan;
• the filter direction;
• the direction of airflow;
• the position of the heating elements;
• the location of the sensors;
• compatibility with the existing ductwork.

The central fan visible during the work

The photo shows the fan motor in the central section of the cabinet.

This fan plays a fundamental role. Its sole purpose is not to push air into the rooms. It must also ensure sufficient airflow across the refrigerant coil and electrical components.

Insufficient airflow can cause:

• overheating of the components;
• an excessively high discharge air temperature;
• tripping of the protective devices;
• ice on the coil in cooling mode;
• excessive noise;
• uneven distribution;
• increased consumption;
• premature motor wear.

An excessive airflow rate can also create problems, including poor dehumidification in summer or significant noise at the grilles.

The fan speed must therefore be adjusted according to the installed capacity, static pressure, and characteristics of the ductwork.

The refrigerant lines visible at the front

The two refrigerant lines connecting the indoor unit to the outdoor heat pump are visible in the photo.

The large-diameter pipe is covered with black insulation. This insulation reduces heat transfer and prevents condensation from forming on the copper.

The smaller line carries liquid refrigerant. It generally remains uninsulated or is protected according to the manufacturer’s requirements.

For the Central-Elios range presented in the documentation, the refrigerant connections are specified as follows:

• 3/8 in. on the liquid side;
• 3/4 in. on the gas side.

Maximum lengths vary according to capacity. The 24,000 and 30,000 BTU models can use up to 164 ft of lines, while the 36,000, 48,000, and 60,000 BTU models can reach 246 ft, subject to charging and installation requirements.

Copper bends that must remain gradual

In such a confined space, it may be tempting to bend the lines very tightly to fit them behind the unit. However, this method can damage the copper.

A flattened line restricts refrigerant flow and can cause abnormal pressures. A bend that is too tight can also weaken the tube and increase the risk of leaks.

We therefore use appropriate bending methods and ensure that the lines are not subjected to permanent tension.

The connections must also remain accessible. A line completely enclosed behind a partition would make future diagnostics more difficult.

How an ELIOS R454B central system operates in a cold climate

A heat pump designed for Quebec winters

According to the manufacturer’s documentation, the Central-Elios range is designed to operate in heating mode down to -30 °C.

The manufacturer also states that the system can provide up to 100% of its rated capacity at -20 °C and retain 69% to 76% of its rated capacity at -30 °C, depending on the model.

This information is important for a home located in Saint-Antoine-sur-Richelieu, where winter temperatures can be very low.

However, actual performance depends on several factors:

• the selected capacity;
• the building’s heat loss;
• the outdoor temperature;
• airflow;
• the condition of the ductwork;
• the quality of the installation;
• the thermostat setting;
• the output of the auxiliary heating.

A heat pump designed for cold weather does not mean that an electric element is never necessary. Auxiliary heating remains an important safeguard during extreme periods.

Inverter technology

The Central-Elios system uses Inverter technology, which allows the compressor to operate at variable speeds.

Instead of always starting at full capacity, the outdoor unit can adjust its output according to demand.

This modulation can improve:

• temperature stability;
• comfort between rooms;
• sound level;
• humidity control;
• seasonal efficiency;
• cycle duration.

The documentation indicates performance of up to 18.3 TRÉS2 and a CPSC2 of up to 8.6, depending on the selected capacity.

The exact capacity of the visible unit cannot be confirmed from the photo. For this reason, we avoid attributing a specific output to this installation without reading the model numbers.

The role of auxiliary electric heating

The electric furnace can accommodate auxiliary heating elements.

The ELIOS brochure indicates that electric coils ranging from 3 to 25 kW are available, depending on the configuration.

These elements can operate:

• during very cold weather;
• when the heat pump is insufficient;
• during certain defrost cycles;
• during a rapid temperature recovery;
• in emergency heating mode.

The element's capacity must be selected carefully.

An element that is too small may not cover the building's heat losses. An element that is too large may require a higher electrical service and unnecessarily increase the power demand.

We therefore check:

• the heating load;
• the heat pump's low-temperature capacity;
• the electrical panel capacity;
• the conductor gauge;
• the circuit breaker size;
• the control sequence;
• the auxiliary heat activation temperature.

The R454B and integrated leak detection

The R454B is a new-generation refrigerant classified as A2L, meaning it has low flammability.

Its use requires compatible tools and methods. Central-Elios documentation states that the units are equipped with an integrated sensor designed to monitor refrigerant leaks.

If a leak is detected, the system can:

• stop the compressor;
• maintain air circulation;
• send a service alert.

This function adds important protection, particularly when the indoor unit is installed in a compact, partially enclosed space.

However, the sensor does not replace the leak test. The connections must be checked using a complete procedure before startup.

Rigorous pressurization and evacuation

Once the lines are connected, we must perform a leak test.

The method generally includes:

1. pressurization with dry nitrogen;
2. a connection check;
3. an observation period;
4. evacuation;
5. a vacuum level measurement;
6. a hold test;
7. valve opening;
8. a verification of the operating parameters.

This step removes air and moisture from the circuit.

Even a small amount of moisture can affect the compressor oil and cause long-term problems.

The quality of this procedure is not visible in the final photo, but it directly affects the heat pump’s reliability.

A cold-climate-certified system

The technical documentation indicates that all combinations in the range presented are certified:

• ENERGY STAR V6.1;
• ENERGY STAR V6.1 cold climate.

Available capacities are 24,000, 30,000, 36,000, 48,000, and 60,000 BTU.

This certification is an important indicator when comparing central systems.

However, it does not automatically guarantee a rebate. Eligibility depends on the program, the exact combination, the reference number, and the conditions in effect at the time of installation.

Rebates must be validated using the exact models

To verify financial assistance, we generally need to confirm:

• the indoor model;
• the outdoor model;
• the certified combination;
• the AHRI number or official reference;
• the heating capacity;
• the purchase date;
• the installation date;
• the building type;
• the required documents.

A brand or general designation such as « ELIOS R454B » is not enough to confirm an amount.

At AirGreen, we prefer to validate the complete combination rather than announce a rebate that may not apply to the installed model.

Integration with the existing ductwork

Above the furnace, we can see several sections of metal ductwork and fittings covered with insulation or a vapor barrier.

In a central replacement, the existing ducts are rarely perfectly aligned with the new cabinet. A transition often has to be fabricated.

A poorly designed transition can cause:

• a restriction;
• noise;
• turbulence;
• an air leak;
• an increase in static pressure;
• a reduction in airflow.

In a compact closet, we must also prevent the transition from encroaching on access to the panels.

The final connection must therefore combine four objectives:

1. ensure the required airflow;
2. limit leaks;
3. respect the available space;
4. preserve service access.

Duct sealing

Duct joints must be properly sealed.

An air leak in a closet or corridor can reduce the amount of air delivered to the rooms and increase the system’s operating time.

It can also draw in dust or odors from the mechanical space.

Sealing improves:

• performance;
• the cleanliness of the system;
• airflow stability;
• comfort;
• the noise level.

The metal tape or sealant used must be suitable for HVAC ducts. General-purpose adhesive tape is not a durable solution.

Condensate drainage

In air conditioning, moisture in the air condenses on the indoor coil.

This water must be discharged through a properly installed drain.

In such a compact closet, a leak could quickly damage:

• the floor;
• the walls;
• objects stored nearby;
• the appliance base;
• the electrical components.

We therefore check:

• the drain slope;
• the tightness of the connections;
• the presence of a trap when required;
• the drain outlet;
• access for cleaning;
• the operation of the safety device, if there is one.

The filter must not be overlooked

The filter protects the coil and fan from dust.

In an area used for storage, the amount of dust may be higher. Objects, boxes, and textiles can also accidentally limit access to the filter.

We recommend keeping the passage clear and never stacking objects against the panels.

A dirty filter can cause:

• reduced airflow;
• an increase in static pressure;
• overheating;
• frost;
• increased consumption;
• uneven comfort.

The owner should check the filter regularly and use the size recommended for the appliance.

Mistakes to avoid in a mechanical closet

Obstructing front access

The panels must be fully removable.

Storing flammable products nearby

A mechanical room should not be used to store products that are incompatible with electrical equipment.

Blocking the filter

The filter must be removable without moving several objects.

Adding a partition without ventilation or clearance

Any modification to the closet must comply with the requirements of the appliance and refrigerant.

Bending refrigeration lines

Copper tubes must not be pushed or used to support objects.

Ignoring a vibration

A vibration may come from a panel that was not properly replaced, a duct, or a support.

Closing multiple dampers

Closing too many grilles can increase static pressure.

Maintenance suited to this configuration

Periodic HVAC maintenance is particularly important when the unit is located in a confined space.

The owner can monitor:

• the condition of the filter;
• noises;
• odors;
• the thermostat codes;
• the presence of water;
• airflow at the grilles;
• temperature variations.

During a professional inspection, we can check:

• the fan;
• the motor;
• the coil;
• heating elements;
• electrical connections;
• the drain;
• sensors;
• static pressure;
• airflow;
• heating sequences;
• the operation of the outdoor heat pump.

Warranties for the Central-Elios line

The brochure indicates a one-year limited warranty on parts and a five-year warranty on the compressor and indoor coil.

Ten-year extended warranties may be available for parts, the compressor, the indoor coil, and, through a third party, labor.

Conditions may vary depending on registration and configuration.

The homeowner should keep:

• the invoice;
• model numbers;
• serial numbers;
• warranty documents;
• the commissioning report;
• maintenance records.

An installation representative of the challenges encountered in Montreal and Greater Montreal

Narrow mechanical closets are common in homes and apartments in Montreal, as well as in Laval, Longueuil, on the North Shore, and on the South Shore.

We regularly encounter:

• hard-to-access equipment;
• modified ductwork;
• insufficient return air;
• spaces shared with storage;
• damaged bases;
• improperly positioned filters;
• refrigerant lines that were too tightly spaced.

Our job is to adapt the new installation without repeating the weaknesses of the previous system.

A result based on integration, not just replacement

This ELIOS R454B electric furnace installation in Saint-Antoine-sur-Richelieu demonstrates that a central unit must be considered as part of an integrated system.

The system must work with:

• the outdoor heat pump;
• the refrigerant lines;
• the duct network;
• the filter;
• the drain;
• the thermostat;
• the auxiliary heating;
• the electrical service;
• the building’s needs.

The main difficulty of this project was the available space. We had to integrate the unit into a very compact closet, maintain access to technical components, and arrange the ductwork without obstructing the hallway.

At AirGreen, we place as much importance on measurements, airflow, connections, and testing as we do on the final appearance. A successful installation must perform well today while also remaining accessible for HVAC maintenance and future repairs.