# MRCOOL Olympus 12,000 BTU wall mount system

> MRCOOL Olympus 12,000 BTU wall mount system (O-ES-12-HP-C-230C-O1 / O-12-HP-WMAH-230C-O) is a 12,000 BTU system from MRCOOL Olympus. It has a wall mount indoor unit, runs on 208/230V, is rated 25.4 SEER2, has an HSPF2 of 10.5, puts out 11,500 BTU/h of heat at 5 °F, uses R-454B refrigerant, and carries a 7-year compressor warranty.

- Line: [MRCOOL Olympus](https://minisplitfacts.com/lines/mrcool-olympus/)
- Category: [Single-zone systems](https://minisplitfacts.com/compare/single-zone/)
- Size tier within its line: 12k
- Status: current
- Data confidence: confirmed (last verified 2026-10-14; [what this means](https://minisplitfacts.com/how-we-compare/#confidence))
- Page: https://minisplitfacts.com/products/mrcool-olympus-12k-wall/

## Specifications

| Spec | Value | Source |
|---|---|---|
| Model number | O-ES-12-HP-C-230C-O1 / O-12-HP-WMAH-230C-O | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Size | 12,000 BTU/h | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Indoor unit style | Wall mount | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Voltage | 208/230V | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Outdoor unit model | O-ES-12-HP-C-230C-O1 | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Indoor unit model | O-12-HP-WMAH-230C-O | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| SEER2 (cooling efficiency) | 25.4 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| EER2 (efficiency at 95 °F) | 13.4 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| HSPF2 (heating efficiency) | 10.5 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Rated cooling capacity | 12,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Heating capacity at 47 °F | 12,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Heating capacity at 17 °F | 12,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Heating capacity at 5 °F | 11,500 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| COP at 5 °F | 1.8 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Heats down to | not published |  |
| Refrigerant | R-454B | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| ENERGY STAR certified | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| ENERGY STAR cold climate | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4428964) (certification, feed, 2026-10-14) |
| Line connection | Flare | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Wi-Fi control | not published |  |
| Indoor sound level (quietest) | 19.5 dB(A) | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |
| Outdoor sound level | not published |  |
| Compressor warranty | 7 years | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-oly-4g-sz-mz-wr-en-01.pdf) (brand, pdf, 2026-10-14) |
| Parts warranty | 5 years | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-oly-4g-sz-mz-wr-en-01.pdf) (brand, pdf, 2026-10-14) |
| Warranty if you install it yourself | Kept | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-oly-4g-sz-mz-wr-en-01.pdf) (brand, pdf, 2026-10-14) |
| Indoor unit size (W×D×H) | 33.74 × 9.09 × 11.81 in | [doxrepo.mrcool.com](https://doxrepo.mrcool.com/mc-cat-en-01.pdf) (brand, pdf, 2026-10-14) |



## The equivalent in other lines

Same category, same size tier (12k), different line:

- [ACiQ Extreme 12,000 BTU ceiling cassette system](https://minisplitfacts.com/products/aciq-extreme-12k-cassette/) — $1,999.99
- [ACiQ Extreme 12,000 BTU slim ceiling cassette system](https://minisplitfacts.com/products/aciq-extreme-12k-cassette-slim/) — $2,149.99
- [ACiQ Extreme 12,000 BTU floor console system](https://minisplitfacts.com/products/aciq-extreme-12k-console/) — $2,049.99
- [ACiQ Extreme 12,000 BTU concealed duct system](https://minisplitfacts.com/products/aciq-extreme-12k-duct/) — $2,099.99
- [ACiQ Extreme 12,000 BTU wall mount system](https://minisplitfacts.com/products/aciq-extreme-12k-wall/) — $1,649.99
- [ACiQ Standard 12,000 BTU 115V wall mount system](https://minisplitfacts.com/products/aciq-standard-12k-115v-wall/) — $1,099.99
- [ACiQ Standard 12,000 BTU ceiling cassette system](https://minisplitfacts.com/products/aciq-standard-12k-cassette/) — $1,739.99
- [ACiQ Standard 12,000 BTU slim ceiling cassette system](https://minisplitfacts.com/products/aciq-standard-12k-cassette-slim/) — $1,889.99


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MiniSplit Facts lists modular tool storage from every brand side by side, with a source for every spec. [How we compare](https://minisplitfacts.com/how-we-compare/). Data as of 2026-10-14.