YORK · Multi-zone heat pumps YORK at AirGreenSold and installed by AirGreen in Montreal, Laval, Longueuil, the South Shore and the North Shore.

YORK multi-zone heat pumps · checked October 26, 2026

YORK multi-zone heat pumps: W or M Series, and how many rooms on a single outdoor unit

From 2 to 5 heads on an outdoor unit of 18,000 to 42,000 BTU/h. The W Series is rated 20.5 to 22 SEER and heats down to −20 °C; the M Series, 16 SEER and −15 °C, at the same rated capacities. Wall, cassette, floor-ceiling or ducted heads can be combined; our listings come with wall heads, the others are quoted on request.

Compare W and M Book my free estimate

W · M

How many rooms? The YORK outdoor units that serve them.

10 YORK outdoor units

W SeriesBTU/h18,00024,00030,00036,00042,000

M SeriesBTU/h18,00024,00030,00036,00042,000

See 2 zones →

8 YORK outdoor units

W SeriesBTU/h18,00024,00030,00036,00042,000

M SeriesBTU/h18,00024,00030,00036,00042,000

See 3 zones →

6 YORK outdoor units

W SeriesBTU/h18,00024,00030,00036,00042,000

M SeriesBTU/h18,00024,00030,00036,00042,000

See 4 zones →

3 YORK outdoor units

W SeriesBTU/h18,00024,00030,00036,00042,000

M SeriesBTU/h18,00024,00030,00036,00042,000

See 5 zones →

Maximum zones: YORK M and W Series brochures, 2019. Greyed out: sizes that do not reach that count.

27YORK multi-zone listings: 14 W and 13 M

2 to 5 heads per outdoor unit

22 SEER 18,000 BTU/h W Series, the top rating

−20 °CW Series heating limit (M: −15 °C)

AirGreen × YORKSold and installed by AirGreenW and M Series2 to 5 headsWall, cassette, floor-ceiling, ductedUp to 22 SEERMontreal · Laval · Longueuil · South Shore · North Shore

01 · Two series

W or M: the same sizes, two efficiency levels.

Both series share the same outdoor unit sizes, 18,000, 24,000, 30,000, 36,000 and 42,000 BTU/h, with the same rated capacities. Efficiency, cold-weather heating and the wall heads set them apart.

W Seriesup to 22 SEER

Efficiency: 20.5 to 22 SEER, heating down to −20 °C.

SEER20.5 to 22HSPF9 to 10.2Heatsdown to −20 °CWall headsDHX (X Series)Max. heads2 · 3 · 4 · 5 · 5Listings1418,000 to 42,000 BTU/h, 2 to 5 heads

M Seriesup to 16 SEER

The same sizes at a lower rating: 16 SEER, same rated capacities as the W.

SEER16HSPF8.2Heatsdown to −15 °CWall headsDHP (P Series)Max. heads2 · 3 · 4 · 4 · 5Listings1318,000 to 42,000 BTU/h, 2 to 5 heads

02 · Size for size

The W and the M at the same outdoor size, row by row.

Same rated capacity: the W gains 4.5 to 6 SEER points and 5 °C of heating range; the M is lighter at 18,000, 24,000 and 36,000 BTU/h, heavier at 30,000 and 42,000.

Outdoor unit

W and M Series at 18,000 BTU/h
Item	W Series	M Series
Outdoor model	DHW18CMB21SAHRI 8581781	DHM18CMB21SAHRI 8581773
Max. heads	2	2
SEER · EER · HSPF	22 · 12.5 · 9	16 · 10.2 · 8.2
Rated cooling · rated heating at 8.3 °C	18,000 · 19,000 BTU/h	18,000 · 19,000 BTU/h
Heating capacity, min. to max.	8,530 to 22,600 BTU/h	8,530 to 22,600 BTU/h
Heats down to	−20 °C	−15 °C
Cooling down to (outdoor)	−18 °C	−5 °C
Min. circuit ampacity (MCA) · max. overcurrent protection (MOCP)	15 A · 25 A	13 A · 20 A
Outdoor unit (W × H × D)	38 × 28 × 16 in.114 lb · 56 dB(A)	35 × 24 × 15 in.95 lb · 56 dB(A)
Total line length	66 ft	66 ft
To the farthest head	33 ft	33 ft
Height difference (up or down)	33 ft	16 ft
Factory charge	56.43 oz	47.61 oz

W and M Series at 24,000 BTU/h
Item	W Series	M Series
Outdoor model	DHW24CMB21SAHRI 8581793	DHM24CMB21SAHRI 8581777
Max. heads	3	3
SEER · EER · HSPF	20.5 · 9.5 · 10.2	16 · 8.2 · 8.2
Rated cooling · rated heating at 8.3 °C	26,000 · 29,000 BTU/h	26,000 · 29,000 BTU/h
Heating capacity, min. to max.	7,500 to 35,000 BTU/h	7,500 to 35,000 BTU/h
Heats down to	−20 °C	−15 °C
Cooling down to (outdoor)	−18 °C	−5 °C
Min. circuit ampacity (MCA) · max. overcurrent protection (MOCP)	21 A · 35 A	20 A · 30 A
Outdoor unit (W × H × D)	38 × 31 × 17 in.153 lb · 59 dB(A)	37 × 28 × 16 in.135 lb · 56 dB(A)
Total line length	197 ft	245 ft
To the farthest head	66 ft	66 ft
Height difference (up or down)	33 ft	33 ft
Factory charge	77.6 oz	77.6 oz

W and M Series at 30,000 BTU/h
Item	W Series	M Series
Outdoor model	DHW30CMB21SAHRI 8581966	DHM30CMB21SAHRI 8581962
Max. heads	4	4
SEER · EER · HSPF	21 · 12 · 10.2	16 · 7.3 · 8.2
Rated cooling · rated heating at 8.3 °C	29,000 · 30,400 BTU/h	29,000 · 30,400 BTU/h
Heating capacity, min. to max.	7,500 to 36,000 BTU/h	7,500 to 36,000 BTU/h
Heats down to	−20 °C	−15 °C
Cooling down to (outdoor)	−18 °C	−5 °C
Min. circuit ampacity (MCA) · max. overcurrent protection (MOCP)	19 A · 30 A	26 A · 45 A
Outdoor unit (W × H × D)	38 × 31 × 17 in.145 lb · 59 dB(A)	36 × 31 × 17 in.153 lb · 56 dB(A)
Total line length	245 ft	245 ft
To the farthest head	82 ft	66 ft
Height difference (up or down)	49 ft	33 ft
Factory charge	98.76 oz	77.6 oz

W and M Series at 36,000 BTU/h
Item	W Series	M Series
Outdoor model	DHW36CMB21SAHRI 8578501	DHM36CMB21SAHRI 8578493
Max. heads	5	4
SEER · EER · HSPF	21 · 12.4 · 10.2	16 · 7.9 · 8.2
Rated cooling · rated heating at 8.3 °C	34,000 · 35,800 BTU/h	34,000 · 35,800 BTU/h
Heating capacity, min. to max.	10,663 to 40,944 BTU/h	10,663 to 40,944 BTU/h
Heats down to	−20 °C	−15 °C
Cooling down to (outdoor)	−18 °C	−5 °C
Min. circuit ampacity (MCA) · max. overcurrent protection (MOCP)	21 A · 30 A	28 A · 45 A
Outdoor unit (W × H × D)	43 × 43 × 17 in.198 lb · 61 dB(A)	36 × 31 × 17 in.161 lb · 59 dB(A)
Total line length	245 ft	245 ft
To the farthest head	82 ft	66 ft
Height difference (up or down)	49 ft	49 ft
Factory charge	128.74 oz	102.29 oz

W and M Series at 42,000 BTU/h
Item	W Series	M Series
Outdoor model	DHW42CMB21SAHRI 8578505	DHM42CMB21SAHRI 8578497
Max. heads	5	5
SEER · EER · HSPF	21 · 10.4 · 10.2	16 · 9.3 · 8.2
Rated cooling · rated heating at 8.3 °C	40,000 · 44,500 BTU/h	40,000 · 44,500 BTU/h
Heating capacity, min. to max.	10,663 to 47,768 BTU/h	10,663 to 47,768 BTU/h
Heats down to	−20 °C	−15 °C
Cooling down to (outdoor)	−18 °C	−5 °C
Min. circuit ampacity (MCA) · max. overcurrent protection (MOCP)	24 A · 30 A	29 A · 50 A
Outdoor unit (W × H × D)	43 × 43 × 17 in.198 lb · 61 dB(A)	40 × 43 × 17 in.225 lb · 58 dB(A)
Total line length	265 ft	265 ft
To the farthest head	82 ft	82 ft
Height difference (up or down)	49 ft	49 ft
Factory charge	128.74 oz	169.31 oz

Outdoor unit rated capacities, SEER, EER and HSPF under AHRI 210/240 (pre-2023 edition, not SEER2), as printed in YORK’s 2020 catalogue. Line limits apply to the whole system.

AirGreen × YORK

YORK designs the system; AirGreen lays it out room by room.

AirGreen counts the rooms with you, picks the series, the outdoor unit and each head within YORK’s combinations, then routes and installs the lines.

What YORK brings

Two series, five sizesW and M from 18,000 to 42,000 BTU/h, same rated capacities.
Four head typesWall, 4-way cassette, floor-ceiling and ducted.
Published combinations175 for the W and 172 for the M, from 2 to 5 heads.

What AirGreen brings

Sold and installed by AirGreenIn Montreal, Laval, Longueuil, the South Shore and the North Shore.
Free visitWe measure the rooms, the insulation, the electrical service and the refrigerant line route.
Clear quoteThe exact model, what is included and the price, in writing.
RBQ 5645-9605-01Subcategories 15.8, 15.10 and 16.

The result: a single outdoor unit, one head per room, in a combination YORK allows.

Compare W and M Book my free estimate

The YORK shop · Multi-zone

All 27 YORK multi-zone systems, right below.

One listing per outdoor unit and head count; each listing gives the heads offered and the AHRI number.

Everything to know · Multi-zone

03 · The heads

Four head types to combine on one outdoor unit.

The cassette, floor-ceiling and ducted heads are shared by both series; only the wall head changes. Our listings come with wall heads; cassette, floor-ceiling and ducted heads are quoted on request. Sizes in BTU/h.

Wall-mounted9,00012,00018,00024,000

DHX (W Series) or DHP (M Series) indoor units, the same as the X and P wall units. Four speeds, turbo, sleep mode; DRCY (W) or DRCPX (M) remote; 5/8 in. drain.

4-way cassette12,00018,00024,000

DHMW…NKB21S, recessed in the ceiling: 22.5 × 22.5 × 9 in., width × depth × height (12,000 and 18,000) or 33 × 33 × 9.5 in. (24,000), PNLMW03 or PNLMW04 panel. Built-in condensate pump; DRCMW remote.

Floor-ceiling9,00012,00018,00024,000

DHMW…NCB21S, hung from the ceiling or mounted low on the wall: 48 × 27.5 × 9 in. (width × depth × height) for every size, 88 to 100 lb. DRCMW remote; 1/2 in. drain.

Ducted9,00012,00018,00021,00024,000

DHMW…NDB21S, hidden above the ceiling, air goes through ducts and grilles. The only 21,000 BTU/h head. Built-in condensate pump; DWCMW wall control as standard.

04 · Sizing

One outdoor unit for the house, one head for each room.

10YORK outdoor units in our catalogue: 5 W and 5 M, from 18,000 to 42,000 BTU/h.

175head combinations YORK publishes for the W Series, from 2 to 5 heads (172 for the M).

21,000BTU/h: the only head size found only in the ducted head.

265 ftof total line length, at most, on the 42,000 BTU/h units.

YORK repeats it under every combination chart: the outdoor unit is sized for the whole building’s load, and each head for its own room’s load.
We don’t install a combination that is not on YORK’s list: that is why each zone page gives the complete list, unit by unit.

05 · Glossary

Multi-zone terms, in plain words.

Zone · head

A zone is a room controlled on its own; the head is the indoor unit that serves it. Each head has its own set point.

Combination

The set of head sizes connected to one outdoor unit, for example 9,000 + 12,000 + 18,000 BTU/h. YORK publishes the list of allowed ones.

Total length

The sum of all the lines between the outdoor unit and the heads. It has its own ceiling, on top of the length to the farthest head.

Height difference

The difference in height between the outdoor unit and a head, whether it sits higher or lower.

Port

The outdoor unit connection a head plugs into: one port per head.

Heating range

The outdoor temperatures within which YORK publishes heating operation: down to −20 °C for the W, −15 °C for the M.

06 · LogisVert

LogisVert: none of our YORK multi-zone systems qualifies.

0/10

None of the 10 AHRI numbers on our 27 listings is on Hydro-Québec’s LogisVert list of October 26, 2026 (“homeowner, existing house” profile), nor in the ENERGY STAR records checked the same day. So we promise no LogisVert amount on these systems.

Frequently asked questions

What people ask us about YORK multi-zone systems.

W Series or M Series for my house?

Size for size, the W is rated 20.5 to 22 SEER versus 16, and heats down to −20 °C versus −15 °C for the M. Rated capacities are the same. The choice is made at the visit, with the number of rooms and the house’s load.

How many rooms can one YORK outdoor unit serve?

Up to five: the 36,000 and 42,000 BTU/h W units and the 42,000 BTU/h M unit take 5 heads. The 36,000 M stops at 4.

Can a wall unit, a cassette and a ducted unit be mixed?

Yes: all four head types connect to the same outdoor unit, within the size combinations YORK publishes; our listings come with wall heads, other heads are quoted on request.

Does a YORK multi-zone qualify for LogisVert?

Not ours: none of the 10 AHRI numbers on our 27 YORK multi-zone listings is on Hydro-Québec’s October 26, 2026 list.

How much line length does a YORK multi-zone allow?

From 66 ft in total on the 18,000 BTU/h units to 265 ft on the 42,000 units, with 33 to 82 ft to the farthest head and 16 to 49 ft of height difference depending on the unit. We map the route at the visit.

AirGreen · Air conditioning & heating

Your YORK multi-zone, laid out room by room and installed by AirGreen.

At the free visit, we count the rooms, pick each head and the outdoor unit within YORK’s combinations, and map the line route.

Book my free estimate 514 316-2973

RBQ 5645-9605-01Subcategories 15.8, 15.10 and 16

Free estimateAt home, no obligation

Sold and installed by AirGreenMontreal, Laval, Longueuil, South Shore and North Shore

Showroom1370 Joliot-Curie Street, unit 712, Boucherville

Sources and dates checked

YORK, Mini-Split Systems catalogue PUBL-7782v6 (November 2020): M and W multi-zone, outdoor units (pp. 24 and 31), indoor units (pp. 23, 25 to 28 and 32 to 35), possible combinations (pp. 29, 30, 36 and 37); copy in our documents, re-read October 26, 2026.
YORK, M Series (PUBL-8258v2) and W Series (PUBL-8259v2) brochures, July 2019: maximum zones per outdoor unit; copies in our documents, re-read October 26, 2026.
Hydro-Québec, LogisVert eligible heat pump list, file of October 26, 2026, “homeowner, existing house” profile, searched by AHRI number.
ENERGY STAR, Certified Air-Source Heat Pumps, dataset w7cv-9xjt, searched by AHRI number on October 26, 2026.
airgreen.ca product pages: outdoor units, head counts and AHRI numbers we carry, read October 26, 2026.

Price on quote. YORK® is a registered trademark, used here to identify the products we sell and install.

YORK multi-zone heat pumps: W or M Series, and how many rooms on a single outdoor unit

How many rooms? The YORK outdoor units that serve them.

W or M: the same sizes, two efficiency levels.

The W and the M at the same outdoor size, row by row.