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MrCool DIY 5th Gen 55K Multi-Zone Condenser (6 zones)
MrCool · DIY 5th Gen Multi-Zone

MrCool DIY 5th Gen 55K Multi-Zone Condenser (6 zones)

Model DIY-MULTI6-55HP230D-O

SCORE6.3 / 10

The strongest 5th Gen condenser, 84% of its rating at 5°F and heat to -22°F, for six zones. Its 20,000 Btu/h minimum needs big loads to run smoothly.

Specs

SpecMrCool DIY 5th Gen 55K Multi-Zone Condenser (6 zones)
Nominal size55,000 BTU
Voltage230V
Rated heat at 47°F55,000 BTU/h
Heat at 17°F44,000 BTU/h
Heat at 5°F46,000 BTU/h
Lowest heating temp-22°F
Max heat at lowest temp21,800 BTU/h
SEER222
HSPF2 (Region IV)10.6
Install typeQuick-connect
Line set in box25 ft
Max line run75 ft
Warranty covers owner installYes
Warranty, parts5 yr
Warranty, compressor7 yr
ENERGY STAR Cold ClimateYes
ENERGY STARYes
RefrigerantR-454B
ZonesUp to 6 indoor units
Minimum heat output at 47°F20,000 Btu/h (whole system)
Electrical208/230V; 43 A MCA, 45 A max breaker
Line limits75 ft per head, 221 ft total, 33 ft height indoor to outdoor

Sources: NEEP ccASHP list · MRCOOL DIY 5th Gen multi-zone install manual · MRCOOL DIY 5th Gen multi-zone service manual (Apr 20, 2026) · MRCOOL DIY 5th Gen limited warranty (rev. 07.03.25)

Before you buy

  • The 4th Gen multi-zone (C suffix, R-410A) is a different system; its 18K ran two zones, not three.
  • On earlier generations owners report idle heads still heating or cooling and rooms overshooting setpoint; there is no long 5th Gen record yet.
  • Line sets are one-time installs; runs past the standard 24.6 ft per head and ducted (AHU) air handlers call for added refrigerant per the manual.
  • Sold on Amazon by a third-party seller in small quantities; condenser only, heads and line sets sold separately.

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