ACiQ Extreme Heat 18,000 BTU

Last updated: October 22, 2026

ACiQ Extreme Heat 18,000 BTU
4.7/5#3 of 22 in 18,000 BTU mini-splits
4.7

ACiQ’s cold-climate line, sold online, keeps most of its rated heat at 5 °F, heats to −22 °F and gets a 12-year compressor warranty once registered. A certified technician has to install it.

  • 18,000 BTUSize
  • 18,000 Btu/hHeat at 5 °F
  • 100%Kept at 5 °F
  • 11 / 21.4HSPF2 / SEER2
  • Pro installInstall
See it at ACiQ

No store we check sells it online; the maker lists where to buy or who installs it.

Pros
  • Keeps 100% of its rated heat at 5 °F: 18,000 Btu/h
  • Keeps heating down to −22 °F
  • 12-year compressor warranty once registered (7 years on parts)
  • Very quiet indoor unit, rated from 19.5 dB(A)
Cons
  • Needs a licensed HVAC installer: a self-install voids the warranty

How it scores

The rating comes from 4 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.

Specifications

Capacity (certified)
Size (nominal)18,000 BTU
Cooling at 95 °F18,000 Btu/h
Heating at 47 °F18,000 Btu/h
Heating at 17 °F (max)19,200 Btu/h
Heating at 5 °F (max)18,000 Btu/h
Heat kept at 5 °F100%
Efficiency (certified)
HSPF2 (Region IV)11
SEER221.4
EER212.5
COP at 5 °F1.92
ENERGY STARENERGY STAR Cold Climate
AHRI certificate216032336
Operating range
Heats down to-22 °F
Cooling range-22 to 122 °F
Installation
Installed byProfessional (sold through installers)
Line set connectionFlare fittings (vacuum pump needed)
Line setup to 98.4 ft
Voltage230 V
RefrigerantR-454B
Indoor unitACIQ-18W-HH-MD
Outdoor unitACIQ-18ZPL-HP230C
Build
Indoor noise19.5–49.5 dB(A)
Outdoor noise59 dB(A)
Wi-FiOptional module
Weightindoor 27.3 lb / outdoor 99.9 lb
Warranty12 yr compressor, 7 yr parts
Warranty with DIY installNo, a licensed installer is required

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