Question 1

How long does a heat pump water heater last?

Accepted Answer

10–15 years, similar to a standard electric water heater and slightly less than the best gas units. Most major brands (Rheem, AO Smith, State, Bradford White) offer 10-year tank warranties.

Question 2

Will I run out of hot water faster than with my gas heater?

Accepted Answer

Not under normal use. Modern HPWHs have a "hybrid" mode that uses electric resistance backup for high-demand periods. The main difference is back-to-back demand — three long showers in a row may stretch a 50-gallon HPWH; the same showers wouldn't faze a tankless gas heater. Sizing up to 65 or 80 gallons solves this for most households.

Question 3

Can I install a heat pump water heater myself?

Accepted Answer

You technically can if you're comfortable with plumbing and 240V electrical work, and many handy homeowners do. But HEAR rebates and most utility rebates require a registered contractor install. If you DIY, you're forgoing $1,000+ in incentives in most states.

Question 4

Does an HPWH work in cold climates?

Accepted Answer

Yes — they pull heat from the surrounding air, not from outside. As long as the install space stays above ~40°F (which most basements and utility rooms do), the heat pump function works fine. In very cold spaces, the unit automatically uses electric resistance backup more often.

Question 5

Should I get a tankless gas or an HPWH?

Accepted Answer

In gas-cheap states with high water demand, tankless gas can have lower operating costs. In electric-cheap or moderate-cost states, HPWH usually wins on total cost of ownership, especially once you factor in the HEAR rebate. A tankless gas unit also locks you into gas service — if you're planning to electrify the rest of the house, the HPWH lets you eventually drop the gas connection entirely.

HPWH rebates in Montana (2026)