Ceiling Cassette CONFORTO MHCAS | 18,000 BTU - R410A
SEER2 (Seasonal Energy Efficiency Ratio)
HSPF2 (Seasonal Heating Efficiency)
EER2 (Instantaneous cooling efficiency)
COP at -8 °C (Heating energy efficiency)
COP at -15 °C (Heating energy efficiency)
COP at -30 °C (MAX)
A large open room, heated and cooled from its centre
The larger a room, the more it matters where the air comes from. The Ceiling Cassette CONFORTO MHCAS | 18,000 BTU - R410A is installed in the ceiling, toward the middle of the space, and distributes the air on four sides rather than from a single wall. The MHCAS18DACFC cassette is paired with the MHSZ118DACFC outdoor unit, whose variable-speed compressor adjusts its speed to the room's demand.
Its certified ratings are 20.0 SEER2, 12.5 EER2 and 9.5 HSPF2. The system is ENERGY STAR certified with the cold-climate designation under ENERGY STAR ID 2495140, its certificate still lists heating capacity at -30 °C, and it qualifies for a $1,872 LogisVert grant.
The challenge of large rooms
In an open area, a wall-mounted heat pump installed at one end heats and cools the zone in front of it well, and the far end much less. You end up raising the set point to reach the farthest corner, and the zone near the unit becomes too warm in winter or too cold in summer.
The cassette changes the geometry of the airflow: placed in the centre, it blows toward all four walls at once, through the louvres around its grille. The distances are shorter, the air mixes better and the temperature is more even from one end to the other. That is the main reason to choose a cassette in a large space.
The spaces this size is meant for
The 18,000 BTU size targets large rooms and open areas: a main floor where the living room, dining room and kitchen form a single space, a large finished basement, an open-plan office, a waiting room, a showroom. In a recent, well-insulated house, it can carry most of an open floor; in an older house with large original windows, it covers a smaller area.
The load calculation done during the visit remains the only honest way to choose. We note the glass area and its orientation, the insulation, the ceiling height and how the space is used, then confirm whether this size fits or another one is more accurate.
Where to place the cassette in an open area
The geometric centre of the room is not always the right spot. We place the cassette between the living zones, away from the range and the hood, and never directly above a workstation, a table or a sofa. We take into account the light fixtures, the joists and the obstacles hidden in the ceiling.
The shape of the room also matters. In an L-shaped space, a single cassette does not always reach the end of the wing, and we say so during the visit rather than promise what the unit cannot do. In heating, warm air tends to stay high: the cassette's position and the louvre setting serve to bring it back toward the floor.
Electrical capacity, checked before the quote
A unit of this size needs a dedicated circuit. In a house whose panel is already heavily loaded by the range, the dryer, the water heater and the baseboards, you have to make sure there is room left. We check the panel capacity during the visit. If an adjustment is needed, it appears in the written quote, not as a surprise on installation day.
Large windows and summer
Open areas often have large glass surfaces, and they are what drives the temperature up in the afternoon. In cooling, the cassette removes that heat and the moisture in the air, which condenses on the coil and flows out through the drain. The EER2 of 12.5 measures full-load efficiency during those hot hours. The variable-speed compressor slows down as soon as the space is comfortable, giving long, steady cycles that dry the air better than repeated starts.
Blinds lowered on the sunny side in the afternoon lighten the unit's work. This simple habit counts for more in a large glazed room than in a small bedroom.
Winter, according to the certificate
The certificate's heating points are measured separately; we report each one as published.
- 15,600 BTU/h at -8 °C (17 °F), with a COP of 2.24, or 87 % of the nominal capacity.
- 16,000 BTU/h at -15 °C (5 °F), with a COP of 1.75, or 89 % of the nominal capacity.
- 8,800 BTU/h at -30 °C, with a COP of 1.27, or 49 % of the nominal capacity.
At -30 °C, the COP of 1.27 remains above that of an electric baseboard, which is 1: even in extreme cold, the cassette produces more heat than it uses in electricity. Its capacity, however, drops by about half. For a large room, we therefore recommend keeping backup heating, the existing baseboards or another system, for those few nights of the year.
How to read an HSPF2 of 9.5
The HSPF2 measures seasonal heating efficiency. It is calculated for a reference climate much milder than Quebec's, with few hours below freezing. It is useful for comparing models with each other, but it does not describe well what happens at -15 °C.
For a Quebec winter, the certified values at the cold points are more telling: a capacity of 89 % at -15 °C and a COP that stays above 1 at -30 °C. The SEER2 of 20.0, for its part, indicates seasonal cooling efficiency: the higher it is, the less the unit uses for the same cooling over the summer. None of these ratings predicts a bill; insulation, settings and the winter itself make the difference.
Variable speed and R-410A
A heat pump moves heat instead of producing it with a resistance element. In winter, the refrigerant captures heat from the outdoor air and the cassette releases it into the room; in summer, the cycle reverses. The variable-speed compressor modulates its speed continuously, without running all-or-nothing, which stabilizes the temperature of a large room.
The system uses R-410A, a refrigerant well known to technicians and found in a large share of the heat pumps installed in recent years. A tight installation, careful evacuation and annual maintenance ensure its reliability.
The $1,872 LogisVert grant
The system is listed in Hydro-Québec's LogisVert program, with $1,872 for the owner of an existing home, according to the list in effect on the installation date. We confirm eligibility before signing and prepare the detailed invoice, model numbers and proof of payment. Our page on the efficient heat pump grant summarizes the program's conditions.
Installation, step by step
- Visit and load calculation. Measuring the space, noting the windows and insulation, checking the electrical panel.
- Ceiling. The cassette is installed between the joists or above a suspended ceiling, fastened to the structure and level, keeping access to the filter and drain. In a drywall ceiling, the opening is cut to the cassette's size, and the grille covers it.
- Drain. Condensate flows out by a continuous slope or, if the route requires it, through a small pump.
- Outdoor unit. On a wall bracket or a ground stand, above the snow line, clear of roof runoff and away from bedroom windows, including the neighbours'.
- Refrigerant lines. They go through a single sealed opening, and a line cover can finish the outdoor run.
- Electrical and commissioning. Connection of the dedicated circuit, leak test, evacuation, checks in heating and cooling, then an explanation of the settings.
Maintenance
Rinse the filter behind the grille every two weeks in season; in a busy office or waiting room, dust builds up faster and more frequent rinsing is justified. Keep the outdoor unit clear of snow and leaves, and plan annual HVAC maintenance of the coils, drain and electrical connections. In winter, white vapour during defrost and a short pause in heating are normal. Our cleaning service takes over when you prefer to hand off the annual visit.
AirGreen, for the life of the installation
A family business active for more than fifteen years in Montreal, Laval, Longueuil, the North Shore and the South Shore, we hold RBQ licences for ventilation, refrigeration and electrical work and carry $5,000,000 in liability insurance. The in-home assessment is free, the quote is in writing, and our financing options let you choose the right unit rather than the cheapest one.
Request your free estimate for the Ceiling Cassette CONFORTO MHCAS | 18,000 BTU - R410A. We measure the space, check the electrical panel and confirm the right size and your grant eligibility before signing.