Home / Comparisons / 15,000 BTU wall heat pumps
FUJITSU AIRSTAGE ORION XLTH and LG ARTCOOL PRESTIGE R32, number by number
Two 15,000 BTU R-32 wall units, both ENERGY STAR cold climate certified, often considered for a large open-plan room. They don’t get to the same result the same way: one moves more air, the other keeps more capacity in extreme cold. Here are their certified values, side by side.
ORION XLTH 15,000 BTU
ASUH15KZAS / AOUH15KZAH1 · AHRI 214888804
Also sold as GENERAL AIRSTAGE ORION XLTH (same AHRI certificate).
View the product page
ARTCOOL PRESTIGE R32 15,000 BTU
KNSAL151A / KUSAL151A · AHRI 215828274
Sold in the United States as LG Art Cool Premier (same model numbers).
View the product pageWhat the electricity costs, in dollars, winter and summer
AirGreen estimate for the same 15,000 BTU/h zone in Montréal, at Hydro-Québec Rate D, taxes included. Both heat pumps are calculated exactly the same way, with the same method as on all our comparison pages; only their certified efficiencies change. Electric baseboards serve as the point of reference.
How this amount is calculated
- Heat needed over the winter. A zone whose heat loss reaches 15,000 BTU/h ( kW) at −23.1 °C, Montréal’s design temperature: kW × 24 h × 4,167 degree-days ÷ (18 − (−23.1)) = kWh of heat for round-the-clock heating, all winter. Heating degree-days (18 °C base) and design temperature: Natural Resources Canada, HOT2000 climate data, Montréal Intl station. With fewer hours a day (the “Heating” slider), the heat is reduced in the same proportion, for the heat pump and the baseboards alike: this is a simplification that ignores the recovery after a temperature setback.
- Electricity for heating. Heat pump: heat × 3.412 ÷ HSPF2 Region V, the AHRI certificate value published by NEEP. Region V is the coldest in the standard, and its calculation includes the electric backup expected when the heat pump is no longer enough. Electric baseboards: 1 kWh of electricity for 1 kWh of heat.
- Electricity for cooling. 15,000 BTU/h ÷ SEER2 × hours a day × 60 days ÷ 1,000: the method of Hydro-Québec’s air conditioning calculator, with the seasonal SEER2 efficiency from the AHRI certificate. The number of hours is a scenario, adjustable above from 1 to 24 h. At 24 h, the calculation assumes rated capacity all day long: that is a maximum, since a variable-speed unit slows down once the room is at the right temperature.
- Price. Hydro-Québec Rate D in effect on April 1, 2026: 7.065¢ per kWh up to 40 kWh a day, 11.142¢ beyond that; the average price, 9.104¢, is the one offered by Hydro-Québec’s calculators. GST and QST included. The system access charge, the same with or without a heat pump, is not counted.
AirGreen method v1.1, November 9, 2026. An estimate is for comparing units under the same conditions. The actual bill depends on the house, the insulation, the settings and how it is used; this amount is not a promise.
One open-plan room, two ways to fill it
Choose the unit and the season: the air plume grows with the maximum airflow published by each manufacturer. In the panel next to it, the certified capacity at each test temperature. More air is not more heat: they are two different measurements, and this page keeps them apart.
Certified capacity, temperature by temperature
Bar: maximum certified capacity; yellow tick: rated certified capacity, when NEEP publishes it. Same scale for both, from 0 to 26,000 BTU/h. Source: AHRI certificates 214888804 and 215828274, NEEP records 392121 and 385474.
Why this page gives no square footage
Two open-plan rooms of the same size can lose very different amounts of heat depending on the insulation, the windows, the ceiling height, the orientation and how airtight the house is. A number of square feet per BTU takes none of these into account.
The right starting point is a room-by-room heat loss calculation at Montréal’s design temperature (−23.1 °C according to NRCan). It is then compared with the certified capacities above, at the temperatures where the house needs them.
Walls, windows and doors, ceiling, air leakage, room volume and the indoor temperature you want.
The maximum certified capacity at −8.3 and −15 °C, then the values published lower down, in “Extreme cold”.
The room dimensions, the windows, the year of construction and your current heating.
Below −15 °C: every published number, at its exact temperature
NEEP certifies both units at −15 °C, at the same temperature. Lower down, their coldest points do not fall in the same place: −26.1 °C for the ORION XLTH, −25 °C for the ARTCOOL PRESTIGE R32. Each number stays at its temperature, with its source; nothing is calculated between two points.
ORION XLTH 15,000 BTU: maximum heating capacity as a percentage of the model’s rated capacity, 15,000 BTU/h, with 21 °C indoors, according to FUJITSU AIRSTAGE brochure FG8153C (revision 4/2025). Vertical line: 100%.
What each manufacturer names
FUJITSU AIRSTAGE brochure FG8153C, the Canadian LG ARTCOOL PRESTIGE R32 brochure and, where the LG brochure is silent, the US LG KSSAL181A sheet (18,000 BTU, same indoor unit according to its published dimensions and weight). Each card says where the information comes from.
ORION XLTH: “no lockout” below −26 °C, heated outdoor base pan (150 W according to the NEEP record), automatic defrost.
ARTCOOL PRESTIGE R32: LGRED, continuous heating advertised down to −25 °C; defrost with a base pan heater (90 W, active at 0 °C and below according to the NEEP record).
ORION XLTH: down to −10 °C outdoors.
ARTCOOL PRESTIGE R32: down to −10 °C outdoors; down to −18 °C with the optional wind baffle and low ambient kit.
ORION XLTH: Powerful, Economy, Energy Saving, Minimum Heat, Occupancy.
ARTCOOL PRESTIGE R32: Jet Cool / Jet Heat, Sleep, auto changeover (US sheet KSSAL181A).
ORION XLTH: Built-in Wi-Fi, AIRSTAGE Mobile app; backlit remote included; optional UTY wall controls.
ARTCOOL PRESTIGE R32: Built-in Wi-Fi, ThinQ app; AKB76044208 remote included (US sheet KSSAL181A).
ORION XLTH: automatic restart after a power failure.
ARTCOOL PRESTIGE R32: automatic restart; “Smart Diagnosis” (US sheet KSSAL181A).
ORION XLTH: washable filter; inverter compressor.
ARTCOOL PRESTIGE R32: self-cleaning indoor coil (US sheet); twin rotary compressor.
The Canadian LG brochure names neither the Wi-Fi nor the remote; AirGreen’s product page shows Wi-Fi. Lines taken from the US sheet are marked as such.
How loud each one is, according to its manufacturer
FUJITSU AIRSTAGE publishes six fan speeds for the ORION XLTH 15,000 BTU. LG publishes four in cooling for the ARTCOOL PRESTIGE R32. Both give a sound pressure in dB(A), measured in an anechoic chamber.
How to read these numbers. dB(A) measures a noise level the way the ear perceives it: the lower the number, the quieter the unit. Each dot is a fan speed published by the manufacturer, from slowest to fastest.
Why this is not a ranking. FUJITSU AIRSTAGE measures in its own anechoic chamber; LG cites the ISO 3745 standard (US sheet). The speeds are not the same: the fastest one on the ARTCOOL PRESTIGE R32 also moves more air. A gap of a few dB(A) can come from the method as much as from the unit.
Indoor unit, in the room
Cooling, every published speed
Outdoor unit, outside
Cooling, highest published speed
Measured by each manufacturer using its own method: read them separately, not as a ranking.
Sources: FUJITSU AIRSTAGE brochure FG8153C and technical manual DR_AS233ES_02; Canadian LG ARTCOOL PRESTIGE R32 brochure and US LG KSSAL181A sheet (ISO 3745 method).
On the wall, outside, in the piping
Indoor units to scale
The ARTCOOL PRESTIGE R32 is 3 5/32 in wider and 3 3/16 in taller. Width × height × depth, according to each brochure.
Outdoor units, scaled to their height
Manufacturer photos scaled to the published height. The FUJITSU AIRSTAGE photo is a three-quarter view: its width in the image cannot be compared directly.
Is your wall wide enough?
Unit width only. Each manufacturer’s installation manual adds a clearance on the sides and at the ceiling; the installer confirms it on site.
| Installation | ORION XLTH | ARTCOOL PRESTIGE R32 |
|---|---|---|
| Maximum piping length | 98 ft | 164 ftMinimum 9.8 ft according to LG. |
| Precharged length | 49 ft | 24.6 ftBeyond that: 0.32 oz/ft according to LG. FUJITSU AIRSTAGE does not give its rate in the brochure. |
| Maximum height difference | 82 ft | 98.4 ft |
| Liquid – gas diameters | 1/4 – 1/2 in | 3/8 – 5/8 in |
| Outdoor unit W × H × D, weight | 31 7/16 × 24 7/8 × 11 7/16 in, 86 lb | 37 13/32 × 32 3/16 in, 135.4 lbThe brochure prints a depth of 10 7/16 in, the same as the indoor unit; it is not repeated here until the LG submittal sheet is available. |
| Indoor unit, weight | 28 lb | 37.7 lb |
| Electrical protectionAccording to the manufacturer | 20 A breaker | Max. protection 30 A (min. circuit ampacity 19 A) |
| Dehumidification | 2.5 L/h | 1.8 L/h3.8 US pints per hour according to LG; 1 US pint = 0.473 L. |
| Advertised heating / cooling range | −26 to 24 °C / −10 to 50 °C | −25 to 18 °C / −10 to 48 °CHeating in wet bulb, cooling in dry bulb, according to LG. |
What people ask about these two 15,000 BTU wall units
Is a 15,000 BTU unit enough for my open-plan room?
It depends on the room’s heat loss, not on its floor area alone. A room-by-room calculation at −23.1 °C gives the heat needed; it is then compared with each unit’s certified capacities at −8.3 and −15 °C, and with the values published lower down.
Which one heats more at −15 °C?
According to NEEP, 21,000 BTU/h maximum for the ORION XLTH and 18,000 BTU/h for the ARTCOOL PRESTIGE R32, at the same test temperature. At 8.3 °C the order is slightly reversed: 25,000 and 25,700 BTU/h.
Why −26.1 °C on one side and −25 °C on the other?
Each manufacturer has its unit tested at the bottom of its advertised range: −15 °F (−26.1 °C) for FUJITSU AIRSTAGE, −13 °F (−25 °C) for LG. The 16,400 and 12,330 BTU/h at these two points are 1.1 °C apart: each one is read at its own temperature.
LG advertises “100% at −25 °C”. Why does the page say 12,330 BTU/h?
The Canadian LG brochure contains both: a text that speaks of 100% at −25 °C, and a table that gives 12,330 BTU/h (69%) at −25 °C for the 15,000 BTU. The AHRI certificate published by NEEP also gives 12,330 BTU/h. The page follows the table and the certificate.
Why is the cost calculated on 15,000 BTU/h for both?
They are two 15,000 BTU wall units. Their certified rated cooling capacities are 14,500 BTU/h (ORION XLTH) and 15,000 BTU/h (ARTCOOL PRESTIGE R32). To compare efficiencies under the same conditions, the estimate uses the common nominal size.
Which one is quieter?
FUJITSU AIRSTAGE publishes 26 to 45 dB(A) in cooling for the ORION XLTH, LG 30 to 49 dB(A) for the ARTCOOL PRESTIGE R32. The speeds and airflows are not the same, and each manufacturer measures with its own method: these numbers place each unit, they do not rank them.
Do both have Wi-Fi?
FUJITSU AIRSTAGE states it for the ORION XLTH (AIRSTAGE Mobile app). For the ARTCOOL PRESTIGE R32, the US LG KSSAL181A sheet lists built-in Wi-Fi with the ThinQ app; the Canadian brochure does not mention it.
Are they eligible for rebates?
Eligibility depends on the official list in effect on the date of purchase. This page promises no amount; the current list is checked at the time of the quote.
All AHRI and NEEP values
| Certified value | ORION XLTH | ARTCOOL PRESTIGE R32 |
|---|---|---|
| Cooling | ||
| 35 °C: min. / rated / max.BTU/h | 3,100 / 14,500 / 19,000 | 3,070 / 15,000 / 24,000 |
| SEER2 | 27.5 | 25.0 |
| EER2 | 14.8 | 15.0 |
| Heating, same conditions | ||
| HSPF2 Region IV / V | 12.7 / 10.1 | 11.2 / 8.4 |
| 8.3 °C: min. / rated / max.BTU/h | 4,150 / 18,000 / 25,000 | 3,070 / 18,000 / 25,700 |
| 8.3 °C: COP min. / rated / max. | 5.07 / 4.59 / 3.26 | 1.64 / 4.67 / 3.07 |
| −8.3 °C: min. / rated / max.BTU/h | 2,600 / 11,400 / 22,000 | 2,934 / 10,900 / 20,200 |
| −8.3 °C: COP min. / rated / max. | 3.81 / 3.44 / 2.35 | 1.34 / 2.90 / 2.04 |
| −15 °C: min. / rated / max.BTU/h | 2,500 / 21,000 / 21,000 | 2,730 / 18,000 / 18,000 |
| −15 °C: COP min. / rated / max. | 3.49 / 2.10 / 2.10 | 1.33 / 1.90 / 1.90 |
| Coldest point — different temperatures, not highlighted | ||
| Test temperature | −26.1 °C (−15 °F) | −25 °C (−13 °F) |
| Capacity min. / max. | 1,900 / 16,400 BTU/h | 2,218 / 12,330 BTU/h |
| COP at maximum capacity | 1.92 | 1.45 |
| Certifications and refrigerant | ||
| ENERGY STAR / cold climate (NEEP) | Yes / Yes | Yes / Yes |
| ENERGY STAR directory, markets listed | United States, Canada | United States, Canada |
| AHRI certificate · NEEP record | 214888804 · 392121 | 215828274 · 385474 |
| RefrigerantGWP per the IPCC (AR4); ASHRAE 34 class | R-32 · GWP 675 · A2L | R-32 · GWP 675 · A2L |
higher marks the higher value of the same measurement, under the same conditions. It is not a recommendation. Capacities and COPs at each point are not highlighted: the order changes depending on the point.
Both are on the AirGreen website.
To choose for your room, talk to our team: bring the room dimensions, the windows, the planned outdoor location and your current heating.
Where each number comes from
Data verified on November 9, 2026. Performance: AHRI certificates and the NEEP database. Dimensions, sound, airflow, piping and features: according to the manufacturer. When a source contradicts the AHRI certificate, the certificate prevails.
Trademarks. FUJITSU AIRSTAGE, ORION XLTH, LG, ARTCOOL and ARTCOOL PRESTIGE are trademarks of their respective owners. Logos are used only to identify the products compared. AirGreen is a dealer for both brands; this page is not produced, sponsored or endorsed by the manufacturers.
Photos: AirGreen and manufacturers, for identification.
Does a figure look wrong? Write to us: every reported figure is checked again.