Mitsubishi Electric MSZ-FX / MUZ-FXNLHZ (FX-Series Hyper-Heat, R-454B — new low-GWP) — specs

Full specifications for the Mitsubishi Electric MSZ-FX / MUZ-FXNLHZ (FX-Series Hyper-Heat, R-454B — new low-GWP). Values are manufacturer- or AHRI-retailer-sourced and cited below; anything unpublished shows as "Not published" rather than guessed. Where a figure is nominal or line-level, we say so inline.

Capacity (BTU)9k–18k (18k model verified)
SEER2 (cooling efficiency)Up to 25.5 (18k)
HSPF2 (heating efficiency)Not published
RefrigerantR-454B (Mitsubishi's 2025 low-GWP transition line)
Cold-climate ratingHyper-Heat cold-climate rated; exact min temp for this model not verified (likely -13°F class — unverified)
InstallationPRO install (EPA-608; contractor)
Zonessingle-zone
WarrantyPRO/Diamond terms (not verified this session)

Price: not shown. Premium brands (Mitsubishi, Daikin, Fujitsu, LG) don't publish MSRP — they sell through contractors — and online-direct prices vary by retailer/promo. We don't quote a price we can't verify; check a retailer or get an installed quote.

Data confidence: HIGH on refrigerant + 18k SEER2; LOW/unknown on HSPF2, exact cold limit, warranty, price

Source: manufacturer / retailer spec sheet. Verify SEER2/HSPF2/capacity per exact SKU on the AHRI Directory.

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Specs compiled from public sources and may change by model year/SKU — the industry is mid-transition from R-410A to R-32/R-454B. Confirm current specs and warranty terms with the manufacturer or dealer before purchase.