# Mitsubishi Electric JX 12,000 BTU 115V wall mount system

> Mitsubishi Electric JX 12,000 BTU 115V wall mount system (MUZ-JX12WL / MSZ-JX12WL) is a 12,000 BTU system from Mitsubishi Electric JX. It has a wall mount indoor unit, runs on 115V, is rated 20 SEER2, has an HSPF2 of 10, puts out 8,600 BTU/h of heat at 5 °F, uses R-454B refrigerant, and carries a 10-year compressor warranty. Lowest in-stock price on file: $1,916.57 at Got Ductless (checked Oct 14, 2026).

- Line: [Mitsubishi Electric JX](https://minisplitfacts.com/lines/mitsubishi-jx/)
- 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/mitsubishi-jx-12k-115v-wall/

## Specifications

| Spec | Value | Source |
|---|---|---|
| Model number | MUZ-JX12WL / MSZ-JX12WL | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Size | 12,000 BTU/h | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Indoor unit style | Wall mount | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Voltage | 115V | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Outdoor unit model | MUZ-JX12WL | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Indoor unit model | MSZ-JX12WL | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| SEER2 (cooling efficiency) | 20 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| EER2 (efficiency at 95 °F) | 12.5 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| HSPF2 (heating efficiency) | 10 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| Rated cooling capacity | 12,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| Heating capacity at 47 °F | 12,200 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| Heating capacity at 17 °F | 7,800 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| Heating capacity at 5 °F | 8,600 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| COP at 5 °F | 1.8 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (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/3893649) (certification, feed, 2026-10-14) |
| ENERGY STAR certified | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| ENERGY STAR cold climate | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/3893649) (certification, feed, 2026-10-14) |
| Line connection | not published |  |
| Wi-Fi control | not published |  |
| Indoor sound level (quietest) | not published |  |
| Outdoor sound level | 51 dB(A) | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Compressor warranty | 10 years | [dw2p0k56b2hr9.cloudfront.net](https://dw2p0k56b2hr9.cloudfront.net/Residential_M_Series_P_Series_and_SMART_MULTI_Split_Air_Conditioner_and_Heat_Pump_Systems_V3_1b7be81e7d.pdf) (brand, pdf, 2026-10-14) |
| Parts warranty | 10 years | [dw2p0k56b2hr9.cloudfront.net](https://dw2p0k56b2hr9.cloudfront.net/Residential_M_Series_P_Series_and_SMART_MULTI_Split_Air_Conditioner_and_Heat_Pump_Systems_V3_1b7be81e7d.pdf) (brand, pdf, 2026-10-14) |
| Warranty if you install it yourself | Licensed installer required | [mitsubishicomfort.com](https://mitsubishicomfort.com/internet-sales) (brand, page, 2026-10-14) |
| Outdoor unit size (W×D×H) | 31.5 × 11.25 × 21.62 in | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Indoor unit size (W×D×H) | 33 × 9.25 × 11.03 in | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |
| Outdoor unit weight | 82 lb | [hvacdirect.com](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) (retailer, page, 2026-10-14) |

## Where to buy

| Store | Price (USD) | Availability | Checked | Link |
|---|---|---|---|---|
| Got Ductless | $1,916.57 | in stock | 2026-10-14 | [View at Got Ductless](https://gotductless.com/products/mitsubishi-msz-jx12wl-muz-jx12wl-20-seer-wall-mounted-standard-system) |
| HVACDirect | $2,195.56 | in stock | 2026-10-14 | [View at HVACDirect](https://hvacdirect.com/12-000-btu-mitsubishi-jx-series-20-seer2-single-wall-mounted-mini-split-heat-pump-system-r454b-muz-jx12wl-msz-jx12wl-199128.html) |

Prices are re-checked weekly; a date more than a month old means the store could not be re-read.

## 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.