Heat Pump List
Menu

Sections

Tools

O-ES-18-HP-C-230B

O-ES-18-HP-C-230B is in the certified data.

Its certified full-speed heating output at 5°F is 11,300 Btu/h, 59% of its 47°F rating (tests at different compressor speeds) in its certified pairing.

MRCOOL · mini-split heat pump

All 110 certified MRCOOL models

O-ES-18-HP-C-230B is in the certified data as of Sep 19, 2026.

Heating at 47°F

19,000

14,900 at 17°F

11,300 at 5°F

Btu/h, certified

2.02 COP at 5°F

Cooling at 95°F

18,000

Btu/h, certified

EER2 12.5 at 95°F

SEER2 23.5

Heating and cooling by outdoor temperature

Certified heating at 5, 17, and 47°F and cooling at 95°F for O-ES-18-HP-C-230B, by outdoor temperature Heating: 11,300 Btu/h at 5°F, 14,900 Btu/h at 17°F, 19,000 Btu/h at 47°F. Cooling: 18,000 Btu/h at 95°F. The bars start at zero. Median of 1.5-ton mini-split models: 14,200 Btu/h at 5°F, 14,800 Btu/h at 17°F, 18,000 Btu/h at 47°F, 18,000 Btu/h at 95°F. 0 5,000 10,000 15,000 20,000 Btu/h 11,300 5°F 14,900 17°F 19,000 47°F 18,000 95°F Outdoor temperature (°F)
  • Heating output
  • Cooling output
  • Median of 1.5-ton mini-split models
  • Example heating load
  • Example cooling load
  • Frosting range, 17 to 45°F

This pairing delivers 19,000 Btu/h of heat at 47°F, 14,900 Btu/h at 17°F, and 11,300 Btu/h at 5°F, 59% of its 47°F rating. It delivers 18,000 Btu/h of cooling at 95°F. At 5°F that is 2,700 Btu/h short of the example heating load of 14,000 Btu/h; at 95°F it is 11,000 Btu/h above the example cooling load of 7,000 Btu/h.

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/h at 5°F to 0 at 65°F, and cooling runs from 0 at 65°F to 7,000 Btu/h 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.

Calculate heating and cooling for your house

AHRI certificate 208552815 · listed by MRCOOL · certified Apr 17, 2026 · 1 pairing carries these values

Rebates where you live

Meets the recorded equipment thresholds of 48 programs in 27 states, provinces, or territories:Alabama (1), Arizona (1), California (2), Colorado (1), Delaware (2), Idaho (2), Illinois (1), Kentucky (1), Maine (2), Maryland (3), Michigan (2), Minnesota (1), Mississippi (2), Nevada (1), New Hampshire (1), New Jersey (7), New York (4), Oregon (2), Pennsylvania (4), Tennessee (1), Texas (2), Utah (1), Vermont (3), Washington (1), Wisconsin (1), British Columbia (3), Newfoundland and Labrador (1).

All 48 programs by state and province

Alabama

Arizona

California

Colorado

Delaware

Idaho

Illinois

Kentucky

Maine

Maryland

Michigan

Minnesota

Mississippi

Nevada

New Hampshire

New Jersey

New York

Oregon

Pennsylvania

Tennessee

Texas

Utah

Vermont

Washington

Wisconsin

British Columbia

Newfoundland and Labrador

Threshold comparisons use the unit’s median certified figures across its pairings, not the pairing selected above. Meeting these thresholds means the equipment may qualify; it does not guarantee approval. Service-area, installation, and product-list requirements also apply.

All rebate programs and their published thresholds

Certified output and power use

Certified output for the selected pairingThe four bars share one scale. The comparison is with the median of 1.5-ton mini-split models. Heating tests run at 70°F indoors. The cooling test runs at 80°F indoors.
Outdoor temperature Certified outputBtu/h One scale vs class median COPat 5°F
5°Ffull speed 11,3003.31 kW −20% 2.02
17°Ffull speed 14,9004.37 kW +1% NR
47°Fnormal speed 19,0005.57 kW +6% NR
95°Fcooling, full load 18,0005.28 kW — NR

EER2 12.5 in that test. SEER2 23.5 over the modeled cooling season.

Power use at each temperature

Electrical input in the 5°F full-speed test
1.64kW
Electrical input in the 95°F cooling test
1.44kW
Seasonal average heating COP
3.17

These exclude backup resistance heat.

Updated Sep 19, 2026 · Methodology

How it compares with other 18,000 Btu heat pumps

1.5-ton mini-split models

This pairing at 5°F
11,300 Btu/h
This unit at 5°F median across its pairings
11,300 Btu/h
Median of 1.5-ton mini-split models at 5°F
14,200 Btu/h
Models in this group
1,110

This unit is above 2% of them, at number 1,083 of 1,110 by heat at 5°F. The middle half of the group runs 13,000 to 18,000 Btu/h.

This size class is defined by cooling capacity, so cooling is not compared here.

Among 18,000 Btu mini-split models, each by its median certified pairing, highest first: 5°F output as a share of its 47°F rating, 1,083rd of 1,110 (tied); HSPF2, 150th of 1,114 (tied). Models without that figure are left out.

Similar ratings at 47°F

These mini-split models share the nominal cooling size. Comparisons use each model’s median certified figures across pairings.

  • MUZ-FS18NA: The same 19,000 Btu/h rating at 47°F; 22,400 Btu/h at 5°F (this model: 11,300).
  • H18FMHD3XPC: The same 19,000 Btu/h rating at 47°F; 19,300 Btu/h at 5°F (this model: 11,300).
  • MUZ-GS18NAHZ: The same 19,000 Btu/h rating at 47°F; 19,000 Btu/h at 5°F (this model: 11,300).

Closest models by heat at 5°F

Every 18,000 Btu (1.5-ton) unit, ranked by cooling efficiency, then heating efficiency

Floor area at the cold test point

The median certified output of 11,300 Btu/h at 5°F matches the size calculator’s heating estimate for these floor areas, rounded to about 10 sq ft. Each range divides that output by the climate band’s heating rates.

Floor area by climate band and house condition
Climate bandHouse conditionBtu/h per sq ftApproximate sq ft
MildDrafty, little insulation24–42270–470
MildTypical16–26430–710
MildTight, well insulated10–18630–1,130
ColdDrafty, little insulation28–52220–400
ColdTypical18–30380–630
ColdTight, well insulated12–22510–940
Very coldDrafty, little insulation32–58190–350
Very coldTypical22–38300–510
Very coldTight, well insulated16–28400–710

This is an estimate, not a house-specific load calculation. Output stays at the 5°F test point for every band; it does not predict output at the band’s winter design temperature.

Certified values for O-ES-18-HP-C-230B

1 pairing · 1 AHRI certificate

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 pairingAll pairings
Heating
Heat output at 47°F normal speed 19,000 Btu/h 19,000 Btu/h
Heat output at 17°F full speed 14,900 Btu/h 14,900 Btu/h
Heat output at 5°F full speed 11,300 Btu/h 11,300 Btu/h
Heat output below 5°F NR NR
Cold output 5°F output as a % of the 47°F rating 59%
COP at 5°F full speed 2.02 2.02
HSPF2 Region IV 10.8 10.8
Cooling
Cooling capacity at 95°F full-load test 18,000 Btu/h 18,000 Btu/h
EER2 at 95°F 12.5 12.5
SEER2 cooling season 23.5 23.5
Cooling at other temperatures NR NR
Equipment and listing
Refrigerant R-410A
Compressor Variable speed
Indoor unit O-18-HP-WMAH-230B 1 indoor unit
FurnaceNo furnace None
Cold-climate designation EPA's designation, as published NC NC
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 O-ES-18-HP-C-230B

Pairings, by indoor-unit class

1 indoor unit · 1 certified pairing

One row per indoor unit certified with this outdoor unit.

Ductless indoor · 1 indoor unit

  1. O-18-HP-WMAH-230B MRCOOL 11,300 Btu/hat 5°F, full speed

    1 pairing · 47°F 19,000 Btu/h · 95°F cooling 18,000 Btu/h · Cold output 59% · COP 2.02

Indoor units in the ductless indoor class
Indoor unit Brand At 5°FBtu/h · full speed At 47°FBtu/h · normal speed At 95°FBtu/h · cooling Cold output% of 47°F rating COP 5°Ffull speed Cold climate Pairings
O-18-HP-WMAH-230B MRCOOL 11,300 19,000 18,000 59% 2.02 NC 1

The share is heat output at 5°F divided by the 47°F rating.

Showing 1 of 1 indoor unit

Sold as, and units with identical certified values

Brands listing this model number

Model number as listed

  • O-ES-18-HP-C-230B 1 pairing

Variants of the same model number

5 units in this group. Basis: identical certified values in the certified data. This grouping is our inference, not a field in the certified data.

4 of 5 shown.

Other model numbers with identical certified values

5 units share this record. Basis: identical certified values in the certified data. This grouping is our inference, not a field in the certified data.

4 of 5 shown.

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

  • O-ES-18-HP-C-230B 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

Cite or print this page

Heat Pump List, “O-ES-18-HP-C-230B — certified heat output”. Certified figures dated , checked daily.
https://heatpumplist.com/model/o-es-18-hp-c-230b