Home / Comparisons / 2-zone multi-zone heat pumps
HITACHI airHome Multi and FUJITSU AIRSTAGE AQUILA XLTH in 2 zones, number by number
Two certified 18,000 BTU/h 2-zone systems, each with two 9,000 BTU wall heads. Their seasonal efficiencies are close: SEER2 23.0 and 22.0, HSPF2 region IV 10.0 and 11.0. Their reserves in extreme cold are not: at −15 °C, NEEP certifies 14,300 and 22,000 BTU/h, and the two certificates stop at different temperatures.
airHome Multi, 2 zones
RAM-G18N2HAA + 2 × RAK-DJ09RHAA · AHRI 216097706
ENERGY STAR: yes · cold climate: no
See the product page
AQUILA XLTH R32, 2 zones
AOUH18KWAH2 + 2 × ASUH09KPAS · AHRI 215447691
ENERGY STAR: yes · cold climate: yes
See the product pageWhat the electricity costs, in dollars, winter and summer
AirGreen estimate for the same 18,000 BTU/h zone in Montréal, at Hydro-Québec rate D, taxes included. Both heat pumps are calculated in exactly the same way, with the same method as on all our comparison pages; only their efficiencies change. For the HITACHI, the NEEP listing does not publish an HSPF2 region V: the winter calculation uses 7.85, the value HITACHI publishes for this ductless combination (February 2025 brochure), outside the certificate. Electric baseboards serve as the reference point.
How this amount is calculated
- Heat needed over the winter. A zone whose heat loss reaches 18,000 BTU/h ( kW) at −23.1 °C, the Montréal design temperature: kW × 24 h × 4,167 degree-days ÷ (18 − (−23.1)) = kWh of heat for 24-hour heating, all winter. Heating degree-days (base 18 °C) and design temperature: Natural Resources Canada, HOT2000 climate data, Montréal Intl station. With fewer hours per day (“Heating” slider), heat is reduced in the same proportion, for the heat pump as for the baseboards: 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 planned for when the heat pump is no longer enough. Electric baseboards: 1 kWh of electricity for 1 kWh of heat. Exception on this page: for the HITACHI, whose NEEP listing gives no region V, the 7.85 value comes from the HITACHI brochure (February 2025, “Non Ducted” column).
- Electricity for cooling. 18,000 BTU/h ÷ SEER2 × hours per 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: 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 force on April 1, 2026: 7.065 ¢ per kWh up to 40 kWh per day, 11.142 ¢ beyond; the average price, 9.104 ¢, is the one Hydro-Québec’s calculators use. GST and QST included. Network access charges, the same with or without a heat pump, are not counted.
AirGreen method v1.1, November 9, 2026. An estimate is used to compare units under the same conditions. The actual bill depends on the house, the insulation, the settings and the use; this amount is not a promise.
What the outdoor unit delivers, and how it is shared
The certificate quantifies the capacity of the outdoor unit, connected to its two heads. The flow below starts from that certified value, at the chosen temperature, and splits toward two rooms. The equal split drawn is an illustration: neither manufacturer certifies each room’s share.
Diagram. Flow width proportional to the outdoor unit’s NEEP certified maximum heating capacity, 21.1 °C indoors. Hatched band: range between two published values, each at its own temperature. Dotted outline: last published value, at a milder temperature.
Below −15 °C: every published number, at its exact temperature
At −15 °C, NEEP certifies 14,300 BTU/h for the airHome Multi and 22,000 for the AQUILA XLTH. Lower down, the two certificates stop at different temperatures: −20 °C for the HITACHI (9,700 BTU/h), −26.1 °C for the AQUILA XLTH (12,060 BTU/h). These two points do not compare directly.
What each manufacturer names
HITACHI multi-zone brochures (December 2024 in French, February 2025 in English) and FUJITSU AIRSTAGE brochure FG2057B (KPAS heads and XLTH units). Each line repeats what the manufacturer writes.
airHome Multi: heating from −20 to 24 °C; snow protection accessory optional.
AQUILA XLTH: heating down to −26 °C, “no lockout”; base heater, activated below 2 °C.
airHome Multi: from −10 to 46 °C outdoors.
AQUILA XLTH: down to −10 °C outdoors.
airHome Multi: R-32 leak sensor.
AQUILA XLTH: Not published by the manufacturer in brochure FG2057B.
airHome Multi: “Smart Eco” and automatic shut-off by motion detector, depending on the model.
AQUILA XLTH: Economy, Minimum Heat, Quiet Mode, Sleep, Dry, Weekly.
airHome Multi: airCloud Go Wi-Fi interface (SPX-WFA01) and airPoint Room H700 thermostat, optional.
AQUILA XLTH: “Wi-Fi Capable” (adapter); “I/O” inputs and outputs.
airHome Multi: stainless steel pre-filter; “FrostWash” coil cleaning; “Mold Guard”.
AQUILA XLTH: “Blue Fin” outdoor heat exchanger.
A feature missing from a column means the document consulted does not name it, not that it is absent. Some HITACHI features depend on the head model; they are checked on the chosen head at quote time.
The noise of each head, according to its manufacturer
HITACHI publishes five speeds for the RAK-DJ09RHAA head, FUJITSU AIRSTAGE six for the ASUH09KPAS head. Both give a sound pressure in dB(A), for one head.
How to read these numbers. dB(A) measures a noise level as 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. Neither brochure states the measuring distance or standard, and the fan speeds do not match one to one. A gap of a few dB(A) can come from the method as much as from the unit.
One 9,000 BTU head, in the room
Cooling, all published speeds
Outdoor unit, outdoors
Highest published value
Measurements taken by each manufacturer with its own method: read them separately, not as a ranking.
Sources: HITACHI multi-zone brochure (February 2025; RAK-DJ09RHAA head: 44 / 42 / 40 / 36 / 29 dB(A), same values in heating; outdoor unit: 52 dB(A) at high speed); FUJITSU AIRSTAGE brochure FG2057B (head: 21 to 40 dB(A) in cooling, 22 to 42 in heating; outdoor unit: 47 and 49 dB(A)).
On the wall, outdoors, in the piping
Wall heads to scale
The HITACHI head is 2 1/8 in narrower and slightly taller (11.0 vs 10 5/8 in). HITACHI dimensions: width × height × depth read from the brochure (780 × 280 × 222 mm).
Outdoor units to scale
33.5 × 29.5 × 11.7 in · 108 lb
32 5/16 × 34 13/16 × 12 3/8 in · 117 lb
Widths at the same scale (W × H × D). The FUJITSU AIRSTAGE unit is 5 5/16 in taller. Photos: AirGreen images of the units sold.
Piping: the total length of the two lines
HITACHI: 165 ft in total, 82 ft per head, 16 ft minimum; the precharged length is not published in the brochure. FUJITSU AIRSTAGE: 98 ft precharged in total, 164 ft maximum, 16 to 82 ft per head. Each line must also respect the per-head limit.
| Installation | airHome Multi | AQUILA XLTH |
|---|---|---|
| Maximum piping length | 165 ft in total, 82 ft per head | 164 ft in total, 82 ft per head |
| Precharged length | Not published by the manufacturer | 98 ft in total |
| Maximum height difference | 66 ft16 ft between the heads. | 49 ft33 ft between the two heads. |
| Liquid – gas diameters | 1/4 – 3/8 in, one pair per head | 1/4 – 3/8 in, one pair per head |
| Outdoor unit W × H × D, weight | 33.5 × 29.5 × 11.7 in, 108 lb | 32 5/16 × 34 13/16 × 12 3/8 in, 117 lb |
| Indoor unit, weightOne 9,000 BTU head | 17.6 lb | 21 lb |
| Electrical protectionAccording to the manufacturer | MOP 25 A (MCA 16 A) | 20 A breaker (minimum circuit ampacity 19.9 A) |
| Advertised heating / cooling range | −20 to 24 °C / −10 to 46 °C | −26 to 24 °C / −10 to 50 °C |
Sources: HITACHI multi-zone brochure (February 2025, “Multi Outdoor” table and the 400 and 650 series wall head table); FUJITSU AIRSTAGE brochure FG2057B and service manual SR_MU008ES_02. Clearances around the outdoor unit are in each installation manual; the installer confirms them on site.
What people ask us about these two systems
Why does the HITACHI winter cost use a value from the brochure?
Because the NEEP listing for certificate 216097706 leaves the HSPF2 region V blank, while our method uses it for winter. HITACHI’s February 2025 brochure publishes 7.85 for the RAM-G18N2HAA with ductless heads; in the same column, its SEER2, EER2 and HSPF2 region IV are exactly those of the certificate. The value is shown as coming from the manufacturer, outside the certificate.
Is the HITACHI cold climate certified?
According to NEEP and the ENERGY STAR directory, the airHome Multi 18,000 is ENERGY STAR certified, but not ENERGY STAR cold climate; the directory lists the United States as its market. The AQUILA XLTH is ENERGY STAR and ENERGY STAR cold climate certified, in the United States and Canada.
What happens colder than −20 °C with the HITACHI?
HITACHI publishes a heating range of −20 to 24 °C for the RAM-G18N2HAA and no capacity below it. FUJITSU AIRSTAGE publishes a point at −26.1 °C and the “no lockout” statement for its XLTH units, without giving capacity below that. The “Extreme cold” table shows, at each temperature, each one’s last published value.
How is the heat shared between the two rooms?
The certificate only quantifies what the outdoor unit delivers with its two heads. Each room’s share depends on the settings, each room’s demand and the line lengths; neither HITACHI nor FUJITSU AIRSTAGE certifies it. A head is also limited by its own size.
Which HITACHI head is used?
HITACHI offers two series of 9,000 BTU wall heads for this system: RAK-DJ09RHAA (400 series) and RAK-GJ09QHAA (650 series). The dimensions, weight and sound on this page are those of the RAK-DJ09RHAA. The RAK-GJ09QHAA is wider (37.4 in) and publishes 27 to 44 dB(A).
Why does the cost estimate use 18,000 BTU/h for both?
Both certificates give a rated cooling capacity of 18,000 BTU/h. The calculation applies the same zone, the same rate and the same method to both; what changes is the HSPF2 region V (7.85 per HITACHI, 9.3 certified for the AQUILA XLTH) and the SEER2 (23.0 and 22.0).
Are these systems eligible for rebates?
Eligibility depends on the official lists in force on the date of purchase, such as Hydro-Québec’s LogisVert list. We check the chosen system at quote time; no amount is promised on this page.
All AHRI and NEEP values
| Certified value | airHome Multi | AQUILA XLTH |
|---|---|---|
| Cooling | ||
| Rated capacity at 35 °C | 18,000 BTU/h | 18,000 BTU/h |
| SEER2 | 23.0 | 22.0 |
| EER2 | 12.5 | 13.5 |
| Heating, same conditions | ||
| HSPF2 region IV / V | 10.0 / —Region V missing from the NEEP listing; 7.85 according to the HITACHI brochure (February 2025), outside the certificate. | 11.0 / 9.3 |
| 8.3 °C: min. / rated / max.BTU/h | 9,000 / 22,000 / 24,000 | 6,800 / 22,000 / 25,000 |
| 8.3 °C: COP min. / rated / max. | 7.54 / 3.31 / 3.52 | 4.53 / 4.39 / 4.39 |
| −8.3 °C: min. / rated / max.BTU/h | 1,200 / 14,900 / 14,900 | 4,700 / 14,800 / 22,800 |
| −8.3 °C: COP min. / rated / max. | 0.82 / 2.50 / 2.30 | 3.28 / 3.24 / 2.58 |
| −15 °C: min. / rated / max.BTU/h | 1,050 / 14,000 / 14,300 | 3,900 / 22,000 / 22,000 |
| −15 °C: COP min. / rated / max. | 0.77 / 1.85 / 1.90 | 2.79 / 2.18 / 2.18 |
| Coldest point — different temperatures, not highlighted | ||
| Test temperature | −20 °C (−4 °F) | −26.1 °C (−15 °F) |
| Capacity min. / max. | 1,000 / 9,700 BTU/h | 2,500 / 12,060 BTU/h |
| COP at maximum capacity | 1.72 | 2.02 |
| Certifications and refrigerant | ||
| ENERGY STAR / cold climate (NEEP) | Yes / No | Yes / Yes |
| ENERGY STAR directory, markets listed | United States | United States, Canada |
| AHRI certificate · NEEP listing | 216097706 · 425199Multi-zone, ductless heads | 215447691 · 455168Multi-zone, ductless heads |
| RefrigerantGWP according to the IPCC (AR4); ASHRAE 34 class | R-32 · GWP 675 · A2L | R-32 · GWP 675 · A2L |
highest marks the highest value of a given measurement, under the same conditions. It is not a recommendation. The HSPF2 line is not highlighted: the HITACHI region V value does not come from the certificate. Capacities and COPs per point are not highlighted: the order changes depending on the point read.
Both are on the AirGreen website.
To choose for your two rooms, talk to our team: bring the size of each room, the planned outdoor location and the distance to each head.
Where each number comes from
Data verified on November 9, 2026. Performance: AHRI certificates and NEEP database; HITACHI HSPF2 region V according to the manufacturer, since the NEEP listing has no value. Dimensions, sound, piping and features: according to the manufacturer. When a source contradicts the AHRI certificate, the certificate prevails.
Trademarks. HITACHI, airHome, FUJITSU AIRSTAGE and AQUILA are trademarks of their respective owners. Logos are used only to identify the products compared. AirGreen is a retailer of both brands; this page is not produced, sponsored or approved by the manufacturers.
Photos: AirGreen and manufacturers, for identification.
Does a data point look wrong? Write to us : every reported data point is checked again.