HVAC Rated

9,000 BTU mini-split heat pump · O-series

TRUST AIR CONDITIONERS OAH09H/O4S4P

Excellent cooling efficiency and very good heating efficiency for a 9,000 BTU mini-split heat pump, and certified for cold climates.

Ranks #51 of 395 9,000 BTU mini-splits for cooling efficiency, and costs about $201 a year to run in a mixed climate like Atlanta.

SEER2
28.1 Cooling efficiency over a season
Excellent · beats 97%
HSPF2
12.0 Heating efficiency over a season
Very good · beats 89%
EER2
16.2 Cooling efficiency on a 95°F day
Excellent · beats 97%
Heat at 5°F
10,800 BTU/h88% of its 47°F output
Average · beats 48%

A good fit if…

  • You want low cooling bills - its SEER2 beats 97% of mini-splits.
  • Your winters get properly cold - it is ENERGY STAR cold-climate certified, with 10,800 BTU/h at 5°F.
  • It will heat most of the year - its HSPF2 beats 89% of mini-splits.
  • You want steady temperatures and quiet running - the compressor varies its speed.

Think twice if…

  • You want the newest refrigerant - it uses R-410A, which is being phased down.

Calculate my running cost

Details

Specifications9,000 BTU, R-410A
General
BrandTRUST AIR CONDITIONERS
Also sold asKepler
Outdoor unit modelOAH09H/O4S4P
SeriesO-series
TypeMini-split heat pump
Nominal size9,000 BTU
CompressorVariable-speed units run longer at low powerContinuously variable
RefrigerantR-410A
Connected (smart) capableNo
On the market sinceOctober 14, 2022
Last certifiedJune 25, 2026
Cooling
SEER2Seasonal efficiency, higher is better28.1 (range 20.2-28.1)
EER2Efficiency at 95°F outdoors13.0-16.2
Cooling capacity9,000 BTU/h
Heating
HSPF2Seasonal efficiency, higher is better10.3-12.0
Capacity at 47°F9,800-12,000 BTU/h
Capacity at 17°F9,000-10,100 BTU/h
Capacity at 5°F10,000-10,800 BTU/h
COP at 5°F2.0 = twice as efficient as a space heater1.80-2.00
ENERGY STAR cold climateYes
Heating output as it gets colder88% kept at 5°F

Every heat pump delivers less heat as the outdoor temperature drops. Certified output of its matchup with IUMW109H/I41P at the standard test temperatures, in BTU/h:

Certified matchups3 indoor units

The same outdoor unit scores differently with each indoor unit. Ask your installer for the AHRI reference number of the exact system you are quoted.

Indoor unitSEER2EER2HSPF2Heat @5°FAHRI ref.
IUMW109H/I41P · cold climate28.116.211.510,600208816914
IUMC409H/I41P · cold climate20.513.010.310,000208816922
IUMDL09H/I43P · cold climate20.213.212.010,800208816930
Same unit, other model numbers1

These model numbers have exactly the same certified ratings and matchups as the TRUST AIR CONDITIONERS OAH09H/O4S4P: the same equipment under another brand, or a variant code for voltage, colour or market. Everything on this page applies to them.

Yearly running cost in 10 large cities$152-$503

At each state's average electricity price and the city's typical heating and cooling hours.

Questions6
What is the SEER2 rating of the TRUST AIR CONDITIONERS OAH09H/O4S4P?
The TRUST AIR CONDITIONERS OAH09H/O4S4P is rated at up to 28.1 SEER2 and 16.2 EER2 for cooling and up to 12.0 HSPF2 for heating. The exact figure depends on the indoor unit it is paired with; across its 3 certified matchups SEER2 ranges from 20.2-28.1.
Is the TRUST AIR CONDITIONERS OAH09H/O4S4P good for cold climates?
Yes. At least one certified matchup meets the ENERGY STAR cold-climate criteria, delivering up to 10,800 BTU/h at 5°F with a COP of 2.00, so it is still 2.0 times as efficient as electric resistance heat at that temperature.
How much does the TRUST AIR CONDITIONERS OAH09H/O4S4P cost to run per year?
At its rated efficiency it costs about $152-$503 a year in electricity in large U.S. cities, depending on climate and local rates - for example $201 in Phoenix and $430 in Minneapolis. The calculator on this page works it out for your city and compares it with your current system.
Is the TRUST AIR CONDITIONERS OAH09H/O4S4P the same as the Kepler ODUMOX330-09HFN1MY5W?
Yes, as far as the certified ratings go. ENERGY STAR lists both model numbers with identical efficiency, capacity and matchups, which means the same outdoor unit sold under a different brand or with a minor variant code (voltage, colour or region). The full list is on this page.
Which indoor units work with the TRUST AIR CONDITIONERS OAH09H/O4S4P?
ENERGY STAR lists 3 certified combinations for this outdoor unit. The highest-rated ones use IUMW109H/I41P, IUMC409H/I41P, IUMDL09H/I43P.
What refrigerant does the TRUST AIR CONDITIONERS OAH09H/O4S4P use?
It uses R-410A. R-410A is being phased down under the EPA AIM Act, and new systems are moving to R-454B and R-32.

Running cost and savings

Pre-filled with this model. Pick your city and what you heat with today; everything else is optional.

Heat pump $206/yrYou save $274/yrSee details ↓
1. Where you live
Adjust heating and cooling hours

Filled in from your city's climate. Change them if you run the system much more or less than usual.

2. The heat pump TRUST AIR CONDITIONERS OAH09H/O4S4P
3. What it replaces
4. Price replace the example with your quote
Heat pump, per year
$206
Current system, per year
$480
You save per year
$274
Payback
12.8 years
Net after 10 years
-$756

Cooling $113Heating $93Electricity used: 1,288 kWhSaved vs. a minimum-efficiency heat pump: $165

Estimates use the unit's rated SEER2 and HSPF2, full-load hours derived from NOAA 1991-2020 degree days, average residential electricity prices from the U.S. EIA (12 months to July 2026) and fuel prices from EIA (2025 for natural gas, week of 2026-10-05 for propane and heating oil). Very cold days that need backup heat are not modelled. Federal minimum for comparison: 14.3 SEER2 / 7.5 HSPF2.

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Source: ENERGY STAR Certified Heat Pumps (U.S. EPA), certification of June 25, 2026. How we use the data.