# Pioneer Quantum Ultra 18,000 BTU one-way cassette system (CYK-24)

> Pioneer Quantum Ultra 18,000 BTU one-way cassette system (CYK-24) (CYK018GMSI24RL) is a 18,000 BTU system from Pioneer Quantum Ultra. It has a ceiling cassette indoor unit, runs on 208/230V, is rated 22.2 SEER2, has an HSPF2 of 12.2, puts out 13,100 BTU/h of heat at 5 °F, heats down to -13 °F by the brand's rating, uses R-454B refrigerant, comes with a 10 ft line set, and carries a 5-year compressor warranty. Lowest in-stock price on file: $2,743 at Pioneer (checked Oct 14, 2026).

- Line: [Pioneer Quantum Ultra](https://minisplitfacts.com/lines/pioneer-quantum-ultra/)
- Category: [Single-zone systems](https://minisplitfacts.com/compare/single-zone/)
- Size tier within its line: 18k
- 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/pioneer-quantum-ultra-18k-one-way-cassette-cyk-24/

## Specifications

| Spec | Value | Source |
|---|---|---|
| Model number | CYK018GMSI24RL | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Size | 18,000 BTU/h | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Indoor unit style | Ceiling cassette | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Voltage | 208/230V | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Outdoor unit model | YN018GMSI24RPG | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Indoor unit model | CK018GMSILDFHG | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| SEER2 (cooling efficiency) | 22.2 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| EER2 (efficiency at 95 °F) | 12.5 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| HSPF2 (heating efficiency) | 12.2 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Rated cooling capacity | 18,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Heating capacity at 47 °F | 18,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Heating capacity at 17 °F | 14,000 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Heating capacity at 5 °F | 13,100 BTU/h | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| COP at 5 °F | 2.24 | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Heats down to | -13 °F | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Refrigerant | R-454B | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| ENERGY STAR certified | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| ENERGY STAR cold climate | yes | [energystar.gov](https://www.energystar.gov/productfinder/product/certified-heat-pumps/details/4520517) (certification, feed, 2026-10-14) |
| Line connection | Flare | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Line set included | 10 ft | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Wi-Fi control | not published |  |
| Indoor sound level (quietest) | 24 dB(A) | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Outdoor sound level | 58 dB(A) | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Room size (brand's claim) | 750 sq ft | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Compressor warranty | 5 years | [pioneerminisplit.com](https://www.pioneerminisplit.com/pages/warranty) (brand, page, 2026-10-14) |
| Parts warranty | 5 years | [pioneerminisplit.com](https://www.pioneerminisplit.com/pages/warranty) (brand, page, 2026-10-14) |
| Warranty if you install it yourself | Kept | [pioneerminisplit.com](https://www.pioneerminisplit.com/pages/warranty) (brand, page, 2026-10-14) |
| Outdoor unit size (W×D×H) | 35 × 13.5 × 26.5 in | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Indoor unit size (W×D×H) | 50.38 × 13.25 × 10 in | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |
| Outdoor unit weight | 92.6 lb | [pioneerminisplit.com](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) (brand, page, 2026-10-14) |

## Where to buy

| Store | Price (USD) | Availability | Checked | Link |
|---|---|---|---|---|
| Pioneer | $2,743 | in stock | 2026-10-14 | [View at Pioneer](https://pioneerminisplit.com/products/pioneer-quantum-ultra-18-000-btu-22-seer2-230v-one-way-cassette-ductless-mini-split-air-conditioner-inverter-heat-pump-full-set) |

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 (18k), different line:

- [ACiQ Extreme 18,000 BTU ceiling cassette system](https://minisplitfacts.com/products/aciq-extreme-18k-cassette/) — $2,249.99
- [ACiQ Extreme 18,000 BTU slim ceiling cassette system](https://minisplitfacts.com/products/aciq-extreme-18k-cassette-slim/) — $2,429.99
- [ACiQ Extreme 18,000 BTU floor console system](https://minisplitfacts.com/products/aciq-extreme-18k-console/) — $2,393.99
- [ACiQ Extreme 18,000 BTU concealed duct system](https://minisplitfacts.com/products/aciq-extreme-18k-duct/) — $2,349.99
- [ACiQ Extreme 18,000 BTU wall mount system](https://minisplitfacts.com/products/aciq-extreme-18k-wall/) — $1,899.99
- [ACiQ Standard 18,000 BTU ceiling cassette system](https://minisplitfacts.com/products/aciq-standard-18k-cassette/) — $1,944.99
- [ACiQ Standard 18,000 BTU slim ceiling cassette system](https://minisplitfacts.com/products/aciq-standard-18k-cassette-slim/) — $2,124.99
- [ACiQ Standard 18,000 BTU floor console system](https://minisplitfacts.com/products/aciq-standard-18k-console/) — $2,088.99


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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.