SZ18H424ZMO
SZ18H424ZMO is in the certified data.
Its certified full-speed heating output at 5°F is 12,700–13,100 Btu/h3.72–3.84 kW, 65–75% of its 47°F rating (tests at different compressor speeds), depending on the pairing.
Sea Breeze · mini-split heat pump
SZ18H424ZMO is in the certified data as of Sep 19, 2026.
- 18,000 Btu (1.5-ton)
- Mini-split
- Variable speed
- US and Canada
Certified heating and cooling
Heating at 47°F
18,0005.28NR
No 47°F rating for this pairing.
14,1004.13NR at 17°F
12,8003.75NR at 5°F
Btu/hkW, certified
2.44NR COP at 5°F
Heating and cooling by outdoor temperature
This pairing delivers 18,000 Btu/h5.28 kW of heat at 47°F, 14,100 Btu/h4.13 kW at 17°F, and 12,800 Btu/h3.75 kW at 5°F, 71% of its 47°F rating. It delivers 18,000 Btu/h5.28 kW of cooling at 95°F. At 5°F that is 1,200 Btu/h0.35 kW short of the example heating load of 14,000 Btu/h4.10 kW; at 95°F it is 11,000 Btu/h3.22 kW above the example cooling load of 7,000 Btu/h2.05 kW.
Each bar is a separate certified test, drawn at its outdoor temperature, starting at zero. The 47°F figure is at normal speed; the 17 and 5°F figures are at full speed. The short dark line on each bar is the median of 1.5-ton mini-split models, one value per model. The shaded 17 to 45°F band is the frosting range: the outdoor coil can frost, and the unit pauses to defrost.
The dashed lines are example loads for a typical area of about 600 sq ft where winters reach 5°F: heating runs from 14,000 Btu/h4.10 kW at 5°F to 0 at 65°F, and cooling runs from 0 at 65°F to 7,000 Btu/h2.05 kW at 95°F, at 1,000 sq ft per ton. A house in a hot climate or with large west-facing windows can need twice as much cooling. They are examples, not your building.
AHRI certificate 208128264 · listed by SEA BREEZE+ · certified Apr 17, 2026 · 1 pairing carries these values
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Threshold comparisons use the unit’s certified figures across its pairings. Programs also set service-area, installation, and product-list requirements.
Certified output and power use
| Outdoor temperature | Certified outputBtu/h | One scale | vs class median | COPat 5°F |
|---|---|---|---|---|
| 5°Ffull speed | 12,8003.75 kW | −10% | 2.44 | |
| 17°Ffull speed | 14,1004.13 kW | −5% | NR | |
| 47°Fnormal speed | 18,0005.28 kW | 0% | NR | |
| 95°Fcooling, full load | 18,0005.28 kW | — | NR |
EER2 13.5 in that test. SEER2 24.0 over the modeled cooling season.
Power use at each temperature
- Electrical input in the 5°F full-speed test
- 1.54kW
- Electrical input in the 95°F cooling test
- 1.33kW
- Seasonal average heating COP
- 3.08
These exclude backup resistance heat.
How it compares with other 18,000 Btu heat pumps
1.5-ton mini-split models
- This pairing at 5°F
- 12,800 Btu/h3.75 kWNR
- This unit at 5°F median across its pairings
- 12,800 Btu/h3.75 kW
- Median of 1.5-ton mini-split models at 5°F
- 14,200 Btu/h4.16 kW
- Models in this group
- 1,110
This unit is above 17% of them, at number 925 of 1,110 by heat at 5°F. The middle half of the group runs 13,000 to 18,000 Btu/h.
Closest models by heat at 5°F
- MSHEA18C2AN1MoovAir · 12,800 Btu/h
- SAK-18-CT2/220VStar Air Kontrol · 12,800 Btu/h
- SHC18VE2AGSlimAir · 12,800 Btu/h
- 4DHP2S18S-1PAirEase, Allied + 3 more · 12,700 Btu/h
- AST-18UW3SBN00Hisense · 12,700 Btu/h
- DEA18HOS25230E8Elios · 12,700 Btu/h
Every 18,000 Btu (1.5-ton) unit, ranked by cooling efficiency, then heating efficiency
Certified values for SZ18H424ZMO
6 pairings · 6 AHRI certificates
This pairing is the one shown above. Under all pairings, a single figure means every pairing agrees and a range means the pairing decides.
| This pairing | All pairings | |
|---|---|---|
| Heating | ||
| Heat output at 47°F normal speed | 18,000 Btu/h5.28 kWNR | 17,000–20,000 Btu/h4.98–5.86 kW |
| Heat output at 17°F full speed | 14,100 Btu/h4.13 kWNR | 12,000–14,100 Btu/h3.52–4.13 kW |
| Heat output at 5°F full speed | 12,800 Btu/h3.75 kWNR | 12,700–13,100 Btu/h3.72–3.84 kW |
| Heat output below 5°F | NR | NR |
| Cold output 5°F output as a % of the 47°F rating | 71%NR | |
| COP at 5°F full speed | 2.44NR | 2.08–2.44 |
| HSPF2 Region IV | 10.5NR | 10.0–10.7 |
| Cooling | ||
| Cooling capacity at 95°F full-load test | 18,000 Btu/h5.28 kWNR | 16,000–18,000 Btu/h4.69–5.28 kW |
| EER2 at 95°F | 13.5NR | 12.5–13.5 |
| SEER2 cooling season | 24.0NR | 20.0–24.0 |
| Cooling at other temperatures | NR | NR |
| Equipment and listing | ||
| Refrigerant | R-410A | |
| Compressor | Variable speed | |
| Indoor unit | WM18H424ZMI | 6 indoor units |
| Furnace | No furnace | None |
| Cold-climate designation EPA's designation, as published | Yes | On some pairings |
| ENERGY STAR Most Efficient EPA's designation, as published | Yes | On every pairing |
| Where it is sold | US and Canada | US and Canada |
| Model string as certified | SZ18H424ZMO | |
Pairings, by indoor-unit class
6 indoor units · 6 certified pairings
One row per indoor unit certified with this outdoor unit.
Ductless indoor · 6 indoor units
-
C18H424ZMI (the pairing on screen) SEA BREEZE+ 12,700 Btu/h3.72 kWat 5°F, full speed
-
CA18H424ZMI (the pairing on screen) SEA BREEZE+ 12,700 Btu/h3.72 kWat 5°F, full speed
-
D18H424ZMI (the pairing on screen) SEA BREEZE+ 13,000 Btu/h3.81 kWat 5°F, full speed
-
FC18H424ZMI (the pairing on screen) SEA BREEZE+ 13,000 Btu/h3.81 kWat 5°F, full speed
-
SCA18H424ZMI (the pairing on screen) SEA BREEZE+ 13,100 Btu/h3.84 kWat 5°F, full speed
-
WM18H424ZMI (the pairing on screen) SEA BREEZE+ 12,800 Btu/h3.75 kWat 5°F, full speed
| Indoor unit | Brand | At 5°FBtu/hkW · full speed | At 47°FBtu/hkW · normal speed | At 95°FBtu/hkW · cooling | Cold output% of 47°F rating | COP 5°Ffull speed | Cold climate | Pairings |
|---|---|---|---|---|---|---|---|---|
| C18H424ZMI (the pairing on screen) | SEA BREEZE+ | 12,7003.72 | 17,0004.98 | 16,0004.69 | 75% | 2.32 | Yes | 1 |
| CA18H424ZMI (the pairing on screen) | SEA BREEZE+ | 12,7003.72 | 19,0005.57 | 16,0004.69 | 67% | 2.16 | NC | 1 |
| D18H424ZMI (the pairing on screen) | SEA BREEZE+ | 13,0003.81 | 20,0005.86 | 17,0004.98 | 65% | 2.40 | NC | 1 |
| FC18H424ZMI (the pairing on screen) | SEA BREEZE+ | 13,0003.81 | 20,0005.86 | 18,0005.28 | 65% | 2.08 | NC | 1 |
| SCA18H424ZMI (the pairing on screen) | SEA BREEZE+ | 13,1003.84 | 19,0005.57 | 18,0005.28 | 69% | 2.30 | NC | 1 |
| WM18H424ZMI (the pairing on screen) | SEA BREEZE+ | 12,8003.75 | 18,0005.28 | 18,0005.28 | 71% | 2.44 | Yes | 1 |
Sold as, and units with identical certified values
What affects the price
We don't have prices. These things drive the cost.
- The size of the unit, and the indoor equipment on the same certificate.
- Whether existing ductwork is reused, altered, or replaced.
- The electrical work: a circuit, a disconnect, and sometimes a panel change.
- Refrigerant line length and how the outdoor unit is mounted.
- Permits and inspection, which vary by municipality.
- Removing and disposing of the old equipment.
- Local labor rates and how busy the season is.
- Rebates and tax credits, which change and have deadlines.
Product history
- SZ18H424ZMO first appeared in the certified data between March 2025 and May 2025.
History and definitions
History
- First certified record
- Most recent certified record
- Measurements reported
- Apr 17, 2026
- Status
- In the certified data
Field definitions
- COP
- Heat delivered for each unit of electricity used. A COP of 2.5 gives 2.5 times the heat of an electric baseboard heater.
- HSPF2
- Heating efficiency over a typical season. Higher uses less electricity.
- SEER2
- Cooling efficiency over a typical season. Higher uses less electricity.
- EER2
- Cooling output divided by electrical input in the 95°F full-load test, in Btu/h per watt.
- Cold output
- Heat output at 5°F as a percentage of the 47°F rating.
- % of rating at 17°F
- Heat output at 17°F as a percentage of the 47°F rating.
NR not in the certified dataNC not cold-climate certifiedSP single pairing onlyVP varies by pairing; see the pairings tableWD withdrawn since the certified data was last read