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SpecDella Serena 18,000 BTU 230VGree Sapphire R32 18,000 BTU 230V
PhotoDella Serena 18,000 BTU 230VGree Sapphire R32 18,000 BTU 230V
Our scoreSCORE7.3 / 10SCORE7.5 / 10
Our takeOur pick for a garage or shop if you'll handle the evacuation: 13,500 BTU/h at 5°F and free parts for a registered DIY install. Nothing is published below 5°F.18,000 BTU/h at 5°F against the Livo 18K's 12,100, for a cold-climate room with a licensed contractor.
Nominal size18,000 BTU18,000 BTU
Voltage230V230V
Rated heat at 47°F18,000 BTU/h18,600 BTU/h
Heat at 17°F15,000 BTU/h19,500 BTU/hbest
Heat at 5°F13,500 BTU/h18,000 BTU/hbest
Lowest heating temp5°F-22°Fbest
Max heat at lowest tempn/a10,800 BTU/h
SEER22227.5best
HSPF2 (Region IV)9.510best
Install typeFlareFlare
Line set in box16.4 ftn/a
Max line run98.4 ft131 ftbest
Warranty covers owner installConditionalNo
Warranty, partsn/a5 yr
Warranty, compressorn/a7 yr
ENERGY STAR Cold ClimateYesn/a
ENERGY STARYesn/a
RefrigerantR-32R-32
Watch out forDella's own 25 ft line set on Amazon is 1/4 x 3/8 in, which doesn't match the 18K's 1/2 in gas line. The listing says "Pre-Charged", but Della's FAQ says the lines are not pre-vacuumed; it is a flare-and-vacuum install. Della's printed manual says the extended warranty is for professional installation; the current web policy gives registered DIY installs replacement parts at Della's discretion. Screenshot it the day you buy. Della also sells Vario, Optima Pro, Hyper Heat and older R410A lines; most owner reports are about those.Amazon Sapphire titles show old SEER figures ("21.5 SEER" on the 24K); confirm the SAPxxHP230V1R32AH/AO model numbers. Gree's submittal prints lower 17°F figures than the certified NEEP ratings; go by NEEP. Gree's warranty applies only to installs by a state certified or licensed HVAC contractor, and claims are contractor-only.
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