Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T)
Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) is a heat pump (hybrid electric) water heater from Ariston with a 45 gallon rated tank and a 69 gallon first-hour rating at a 3.83 UEF — 848 kWh/yr certified use, 45.8 in tall.
Our take
Move up to Ariston's 45-gallon variant and the numbers improve across the board: 3.83 UEF at the 79th percentile of the class (about $144 a year, roughly $470 less than a standard electric tank), a 69-gallon first-hour rating that beats the cohort median by nearly 5 gallons, and the same R-513A refrigerant with less than half the GWP of the class-standard R-134a. Height is the class-median 45.8 inches. Connected-capable, 240 V at 21 A. Sold under 2 brand names — Ariston and Lennox — with identical certified specs.
Best for: Above-median everything with a lower-GWP refrigerant.
Trade-off: Standard-format height; the sub-40-inch installs need its shorter sibling.
Efficiency
Uniform Energy Factor (UEF)
3.83
Annual electricity use
848 kWh/yr
Recovery efficiency
437 %
General
Fuel
Electric
Capacity
First-hour rating
69 gal
Rated storage volume
45 gal
Draw pattern
Medium
Heat pump
Heat pump type
240 Volt Integrated HPWH
Refrigerant (GWP)
R-513A (GWP:630)
Compressor low-temp cutoff
35 °F
Installation
Input voltage
240
Max current draw
21 A
Smart features
Smart / connected capable
Yes
Dimensions
Height
45.8 in
Diameter
18.2 in
Certification
ENERGY STAR certified
Yes
Who is the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) for?
Its 69 gallon first-hour rating suits a
household of 3–4 people under DOE sizing guidance.
Estimated running cost: about $144/year at the national
average electricity rate (848 kWh/yr certified use).
Needs a 240 V circuit; at 21 A max draw plan for a 30 A breaker (NEC 125% continuous-load rule).
The heat pump compressor operates down to 35 °F ambient — below that, backup
elements take over.
Also sold as
The Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) is certified hardware that Ariston and its partner brands
publish under 2 names. The same specifications apply to every
variant:
Is the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) ENERGY STAR certified?
Yes, the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) holds a current ENERGY STAR certification for water heating efficiency (UEF 3.83).
How much does the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) cost to run per year?
About $144 per year at national average energy rates, based on its certified annual energy use under the DOE test draw pattern. Your rate and usage change this figure.
What electrical circuit does the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) need?
The Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) runs on a 240 V circuit drawing up to 21 A; per the NEC 125% continuous-load rule plan for at least a 30 A breaker (check the installation manual for the required circuit).
Is the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) a smart water heater?
Yes, the Ariston Heat Pump Water Heater 40-Gallon (ARIHPWH-50-T) is connected-capable, with app control and eligibility for most utility demand-response programs.
