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FUJITSU AIRSTAGE ORION XLTH and ORION XLTH+: what the “+” changes
Same brand, same size, same refrigerant. The “+” means a different outdoor unit, a different indoor unit and a different AHRI certificate. This page shows what the certified records and FUJITSU AIRSTAGE’s documents give that is different, and where the two stay close.
FUJITSU AIRSTAGEORION XLTH 12,000 BTU
ASUH12KZAS / AOUH12KZAH1 · AHRI 214888802
View the product page
FUJITSU AIRSTAGEORION XLTH+ 12,000 BTU
ASUH12KTAS / AOUH12KTAP1 · AHRI 216018256
View the product pageWhat the electricity costs, in dollars, winter and summer
AirGreen estimate for the same 12,000 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 12,000 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. 12,000 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.
The “+” adds reserve when it gets cold
The two maximum capacity curves, overlaid. The colored band is the gap, at the temperatures where both units are measured the same way: NEEP certified from 8.3 to −15 °C, then taken from the FUJITSU AIRSTAGE technical manuals at −26.1 °C. In rated capacity the order is reversed: the “+” does not raise the rated capacity, it raises the maximum.
Two characters on the indoor unit, two on the outdoor unit
The dark boxes are the ones that change from one model to the other. FUJITSU AIRSTAGE names its series with these letters: 12KZAH1 for the ORION XLTH, 12KTAP1 for the ORION XLTH+. The documents consulted give no official key for each letter, so this page does not translate them one by one.
What the manuals describe differently
Specific to the ORION XLTH
- ASUH12KZAS indoor unit: 38 9/16 × 11 × 9 7/16 in, 28 lb.
- Indoor heat exchanger 796 mm wide, in four sections: 2 × 10, 2 × 8, 1 × 4 and 1 × 4 rows × columns of tubes.
- AOUH12KZAH1 outdoor unit: 31 7/16 × 24 7/8 × 11 7/16 in, 86 lb.
- Heating range published down to −26 °C, “no lockout”.
Common to both
- R-32, 12,000 BTU/h certified rated cooling.
- 150 W heated base pan, depending on temperature and mode (NEEP records).
- Built-in Wi-Fi, AIRSTAGE Mobile app; backlit remote included.
- Economy, Energy Saving, Powerful, Minimum Heat and Occupancy modes.
- Cooling down to −10 °C outdoors.
Specific to the ORION XLTH+
- ASUH12KTAS indoor unit: 35 3/16 × 11 5/8 × 11 in, 31 lb.
- Indoor heat exchanger 718 mm wide, in three sections: 3 × 24, 1 × 4 and 1 × 6.
- AOUH12KTAP1 outdoor unit: 32 5/16 × 28 3/16 × 12 3/8 in, 93 lb.
- Heating range published down to −30 °C, “no shutoff device”.
Dots: one dot per tube of the indoor heat exchanger described (rows × columns). FUJITSU AIRSTAGE technical manuals DR_AS233ES_02 (ORION XLTH) and DR_AS242ES_04 (ORION XLTH+). The AOUH12KZAH1 compressor is not described in the documents consulted: no compressor comparison here. Dimensions: width × height × depth.
Below −15 °C: every published number, at its exact temperature
At −15 °C, both are certified at the same point. At −26.1 °C, both FUJITSU AIRSTAGE technical manuals give a value, calculated the same way. At −30 °C, only the “+” is measured.
ORION XLTH · maximum capacity as % of 12,000 BTU/h (brochure FG8153C)
ORION XLTH+ · maximum capacity as % of 12,000 BTU/h (brochure FG8154D)
Base: the model’s rated capacity, 12,000 BTU/h, with 21 °C indoors, according to each brochure (revision 4/2025). Same scale for both strips; vertical line: 100%.
The same lists, a few different details
FUJITSU AIRSTAGE brochures FG8153C (ORION XLTH) and FG8154D (ORION XLTH+), revision 4/2025.
ORION XLTH: heating down to −26 °C, “no lockout”; heated base pan.
ORION XLTH+: heating down to −30 °C, “no shutoff device”; heated base pan.
ORION XLTH: down to −10 °C outdoors.
ORION XLTH+: down to −10 °C outdoors.
ORION XLTH: Powerful, Economy, Energy Saving, Minimum Heat, Occupancy.
ORION XLTH+: the same five modes.
ORION XLTH: Built-in Wi-Fi, AIRSTAGE Mobile; UTY-RVRU, UTY-RNRUZ5, UTY-RHRY, UTY-RSRY wall controls.
ORION XLTH+: same wall controls, with the UTY-TWRXZ4 communication kit.
ORION XLTH: automatic restart and defrost.
ORION XLTH+: automatic restart and defrost.
ORION XLTH: inverter compressor.
ORION XLTH+: DC rotary compressor, electronic expansion valve (service manual).
Same method, two indoor units
Here, one brand measures both of its units in its own anechoic chamber: the comparison reads speed by speed, keeping in mind that the airflows differ.
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 FUJITSU AIRSTAGE, from slowest to fastest.
Why this is not a ranking. The two units do not move the same volume of air at each speed (200 to 518 and 206 to 512 CFM in cooling). A gap of one or two dB(A) is not always audible in a room.
Indoor unit, in the room
Cooling, six published speeds
Outdoor unit, outside
Cooling, highest published speed
Same manufacturer, same anechoic chamber: the differences read speed by speed, keeping in mind that the two units do not move the same volume of air.
Shorter, narrower, taller
Indoor units to scale
The “+” unit is 3 3/8 in narrower, 5/8 in taller and 1 9/16 in deeper.
Is your wall wide enough?
Unit width only; the installation manual adds clearances that the installer confirms on site.
| Installation | ORION XLTH | ORION XLTH+ |
|---|---|---|
| Maximum piping length | 82 ft | 66 ft |
| Precharged length | 49 ft | 49 ft |
| Maximum height difference | 66 ft | 49 ft |
| Liquid – gas diameters | 1/4 – 3/8 in | 1/4 – 3/8 in |
| Outdoor unit W × H × D, weight | 31 7/16 × 24 7/8 × 11 7/16 in, 86 lb | 32 5/16 × 28 3/16 × 12 3/8 in, 93 lb |
| Indoor unit, weight | 28 lb | 31 lb |
| Electrical protectionAccording to the manufacturer | 15 A breaker | 20 A breaker |
| Heated base panManufacturer’s statement to NEEP | Yes, 150 W | Yes, 150 W |
| Dehumidification | 1.9 L/h | 1.8 L/h |
| Advertised heating / cooling range | −26 to 24 °C / −10 to 50 °C | −30 to 24 °C / −10 to 50 °C |
Brochures FG8153C and FG8154D (revision 4/2025). AirGreen’s product pages show the same outdoor unit rendering for both models; the published dimensions, however, differ.
What people ask about the “+”
Is it the same indoor unit with a different outdoor unit?
No. The model numbers change on both sides (ASUH12KZAS and ASUH12KTAS), so do the dimensions, and the manuals describe two different indoor heat exchangers. Each pair has its own AHRI certificate.
How much more does the “+” heat at −15 °C?
According to NEEP, 20,500 BTU/h maximum versus 16,600, or 3,900 BTU/h more, at the same test point. At −26.1 °C, the FUJITSU AIRSTAGE technical manuals give 15,300 and 12,200 BTU/h.
Why is the ORION XLTH’s rated capacity higher?
At 8.3, −8.3 and −15 °C, the certified rated capacity of the ORION XLTH is 16,000, 10,000 and 16,600 BTU/h, versus 15,300, 9,600 and 16,200 for the ORION XLTH+. The rated capacity is a set point chosen for the test; the “+” shows its gap at maximum.
Why −26.1 °C on one side and −30 °C on the other in the NEEP records?
Each unit is measured at the bottom of its advertised range: −15 °F (−26.1 °C) for the ORION XLTH, −22 °F (−30 °C) for the “+”. To read both at the same temperature, the page uses the technical manuals at −26.1 °C.
Is the “+” quieter?
At the lowest speed, both are published at 23 dB(A); at the highest, 43 and 44 dB(A) in cooling. At the intermediate speeds, the ORION XLTH is published slightly lower, with slightly less airflow.
Does the operating cost change much?
The calculation above uses the certificates' HSPF2 Region V (10.1 and 11.3) and SEER2 (30.5 and 31.5). Adjust the heating and cooling hours to see the difference in your scenario.
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 | ORION XLTH+ |
|---|---|---|
| Cooling | ||
| 35 °C: min. / rated / max.BTU/h | 3,100 / 12,000 / 16,000 | 3,100 / 12,000 / 17,300 |
| SEER2 | 30.5 | 31.5 |
| EER2 | 16.0 | 16.7 |
| Heating, same conditions | ||
| HSPF2 Region IV / V | 12.7 / 10.1 | 13.7 / 11.3 |
| 8.3 °C: min. / rated / max.BTU/h | 3,500 / 16,000 / 23,600 | 4,500 / 15,300 / 27,300 |
| 8.3 °C: COP min. / rated / max. | 5.13 / 4.64 / 3.07 | 6.28 / 4.87 / 3.59 |
| −8.3 °C: min. / rated / max.BTU/h | 2,200 / 10,000 / 18,700 | 2,900 / 9,600 / 22,800 |
| −8.3 °C: COP min. / rated / max. | 3.39 / 3.45 / 2.44 | 4.72 / 3.47 / 2.59 |
| −15 °C: min. / rated / max.BTU/h | 1,950 / 16,600 / 16,600 | 2,500 / 16,200 / 20,500 |
| −15 °C: COP min. / rated / max. | 3.36 / 2.16 / 2.16 | 3.86 / 2.62 / 2.18 |
| Coldest point — different temperatures, not highlighted | ||
| Test temperature | −26.1 °C (−15 °F) | −30 °C (−22 °F) |
| Capacity min. / max. | 1,400 / 12,200 BTU/h | 1,900 / 15,300 BTU/h |
| COP at maximum capacity | 1.81 | 1.76 |
| Certifications and refrigerant | ||
| ENERGY STAR / cold climate (NEEP) | Yes / Yes | Yes / Yes |
| AHRI certificate · NEEP record | 214888802 · 392122 | 216018256 · 384143 |
| 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 between rated and maximum.
Both are on the AirGreen website.
To choose for your home, talk to our team: bring the room dimensions, 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, piping, heat exchangers and features: according to the manufacturer. When a source contradicts the AHRI certificate, the certificate prevails.
Trademarks. FUJITSU AIRSTAGE, ORION XLTH and ORION XLTH+ are trademarks of their owner. Logos are used only to identify the products compared. AirGreen is a dealer for the brand; this page is not produced, sponsored or endorsed by the manufacturer.
Photos: AirGreen and manufacturer, for identification.
Does a figure look wrong? Write to us: every reported figure is checked again.