Appliances / Heat pump water heaters / Ariston
Ariston ARIHPWH-40
37 gal · 240-volt integrated heat pump water heater
Check the price at the store, then add $2,145 of electricity to get the true cost. We may earn a commission if you buy through these links; as an Amazon Associate we earn from qualifying purchases.
- Price. Check what it costs at the store.
- Plus running cost. Add $2,145 of electricity over 13 years. That is the part the price tag hides.
- Compare. Pick your state below, then check the cheaper-to-run models of the same size.
About the Ariston ARIHPWH-40
The Ariston ARIHPWH-40 is a 37 gal 240-volt integrated heat pump water heater certified by ENERGY STAR. Its official test figure is 907 kWh of electricity a year, which at the U.S. average price of 18.19¢ per kWh comes to $165 a year, or $2,145 over a typical 13-year life.
For the same hot water, a standard electric tank water heater would use about 3,529 kWh a year, so this model uses 74% less electricity and saves about $477 a year.
Among 371 240-volt integrated models it ranks #149 for running cost. The cheapest model of this type would save $624 in electricity over 13 years, though it may differ in size and features.
If you want the same type and a similar size for less to run, the Friedrich PROH40 T2 FD400-15 uses 643 kWh a year and would save about $624 over 13 years.
Listed features: smart / app control.
Cost to run where you live
907 kWh a year (ENERGY STAR test figure) × 18.19¢ per kWh, the average residential price in the U.S. for Jan–Aug 2026 (EIA). Your bill depends on your utility and how you use it.
Cheaper to run, same type and size
Or see every under 50 gallons model ranked.
| Friedrich PROH40 T2 FD400-15 | 36 gal | $117/yr | saves $624 |
| Rheem PROPH40 T2 RH375-15 | 36 gal | $117/yr | saves $624 |
| Rheem PROPH40 T2 RH400-15 | 36 gal | $117/yr | saves $624 |
| Rheem XE40T10H22U0 | 36 gal | $117/yr | saves $624 |
Specs
| Brand | Ariston |
| Model | ARIHPWH-40 |
| Type | 240-volt integrated |
| Energy use | 907 kWh / year |
| Federal maximum for this type | 3529 kWh / year |
| Size | 37 gal |
| Width | 18.2 in |
| Features | Smart / app control |
| Tank size | 37 gal |
| First-hour rating | 66 gal |
| Efficiency (UEF) | 3.58 |
| Usage pattern | Medium-Usage |
| Voltage | 240 |
| Tank height | 37.6 in |
| Tank diameter | 18.2 in |
Specs and energy use from the ENERGY STAR certified products list (U.S. EPA). An asterisk in a model number stands for colour or finish codes. HouseholdLeak is not affiliated with ENERGY STAR or the EPA.
Questions people ask
How much does the Ariston ARIHPWH-40 cost to run?
About $165 a year at the U.S. average electricity price (18.19¢/kWh), based on its ENERGY STAR rating of 907 kWh a year. In a state with expensive power it can be much more; pick your state on this page to see your number.
How much will the Ariston ARIHPWH-40 cost in electricity over its life?
About $2,145 over 13 years, a typical life for a heat pump water heater. Add that to the price you pay to get the true cost to own.
Is the Ariston ARIHPWH-40 energy efficient?
Yes. It is ENERGY STAR certified and uses 74% less electricity than a standard electric tank water heater.
Is there a cheaper water heater to run of the same type and size?
Yes. The Friedrich PROH40 T2 FD400-15 uses 643 kWh a year, about $624 less in electricity over 13 years.
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