Ariston NUOS Side-Connect 50 Gal

Last updated: October 22, 2026

Ariston NUOS Side-Connect 50 Gal

A non-Midea design with a leak sensor built in and a 10-year tank and parts warranty, sold through plumbing dealers. It is louder than most here.

  • 50 galSize
  • 3.75UEF
  • 68 galFirst hour
  • 240 VPower
  • 35 °FRuns down to
  • 10 yr tankWarranty
See it at Ariston

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

Pros
  • Built-in leak sensor
  • The heat pump keeps running in rooms down to 35 °F
  • Built-in Wi-Fi: set schedules and vacation mode from the Ariston NET app
Cons
  • No labor cover in the published warranty
  • Louder than most at 49.1 dB(A); best kept away from bedrooms

How it scores

The rating comes from 5 measured or published factors, each scored 0-100 against fixed reference points for its size. How we rank explains each one.

Specifications

Model numberARIHPWH-50
Ratings (ENERGY STAR)
Size (nominal)50 gal
Tank volume (measured)45 gal
Uniform Energy Factor3.75
First-hour rating68 gal
Draw patternMedium
Yearly energy use867 kWh
Heat pump cut-off (low)35 °F
Sound level49.1 dB(A)
ENERGY STAR ID3942616
Installation
Power240 V
Circuit30 A, 208/240 V
Backup element4,500 W
Operating air range36 to 120 °F
Minimum room size700 cu ft
Size45.8 in tall, 18.2 in across
RefrigerantR-134a
Features
Wi-FiBuilt in
AppAriston NET
Demand response port (CTA-2045)Yes
Leak detectionYes
ModesComfort, Green, Fast, Electric, Vacation
Warranty and models
Warranty10 yr tank, 10 yr parts
Also sold asAmerican Standard ASHPWH-50*****, Lennox WHHP050T45MD240S****
Released2024-12

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