Water heaters
A. O. Smith ProLine XE Voltex AL (HPTS-66) Heat Pump Water Heater, 66 gal
Prices are the equipment only — the appliance, before install labour. Every product in this catalogue currently has at least one real, seller-observed equipment price (see the SKU verification and price observation notes on each product). Get contractor quotes for the install itself, especially for anything needing new electrical circuits or condensate drainage.
66-gallon heat pump water heater with a UEF of 4.02 -- among the highest in our water heater set, just behind GE's Profile GeoSpring Smart Hybrid at 4.50. Sold under A. O. Smith's 'ProLine XE Voltex AL / Smart Hybrid' line — a different, retail-exclusive 'Signature Series' name is used for a different model-number family at Lowe's, so don't cross-shop the names.
Our take
A. O. Smith and Rheem between them make most of the water heaters sold in America, including many that carry other brand names. The HPTS-66 splits the difference on size in a way that suits a lot of houses better than the standard 50 or 80, and its efficiency is best-in-class on paper. Owner reports on this platform's ECC compressor-fault code recurring across replacement units are worth reading before assuming the efficiency number is the whole story. Availability skews toward plumbing wholesale rather than big-box retail.
Best for
Three to five person households wanting maximum efficiency without an 80-gallon footprint.
Watch out for
Wholesale distribution means a plumber generally sources it, so you have less price transparency than with a retail unit. See the field reliability notes on this platform's compressor fault code.
What sellers are actually charging
The lowest in-stock, full-equipment price we've seen is $2,809, at SupplyHouse.com, seen 2026-08-16. Every listing from the last 30 days, newest first, is below — prices change, click through to check before you act on any of them.
| Seller | What you get | Price | Stock | Seen |
|---|---|---|---|---|
| SupplyHouse.com
online retailer |
equipment system | $2,809 | in stock | 2026-08-16 |
Equipment price is not installed price. The listings above are what the hardware costs. Installation — labour, electrical, refrigerant lines, permits, removing the old system — is typically a similar amount again, and varies more between contractors than between brands. Where we have an installed figure it is labelled as such and comes from someone who actually installs.
Model number check: mismatch
'Signature Series' is real A.O. Smith branding, but it names a different, retail-exclusive Lowe's model family (e.g. HPS10-66H45DV), not the wholesale HPTS- SKU this catalogue actually prices. The HPTS-6x/8x platform's correct current branding is 'ProLine XE Voltex AL' ('Smart Hybrid'), confirmed on A.O. Smith's own product page and independently at two wholesale distributors. Catalogue line label corrected.
What owners and installers report
Collected from trade forums, owner communities and video reviews. Every report links to the original. We synthesise and quote briefly — we don't republish other people's writing.
Reliability and failures
What breaks, when, and how often — from people several years in.
Owner reports replacing an A.O. Smith hybrid water heater three times in roughly two years for a recurring ECC (compressor) fault code. Warranty covered parts but the maker stopped covering labor after the second replacement, leaving the owner to pay a plumber directly.
“I've had to replace new ao smith hybrid water heater 3 times in last couple years due to ECC compressor fail code.” — forum participant homeowner
AOSmith hybrid water heaters wasted $ · Owner/trade forums (misc.) · 2024-06-01 · read it in context
Voltex AL Smart Hybrid unit installed March 2025 began failing about 13 months later with error codes; a $400 coil repair under a parts-only warranty was followed by circuit-breaker issues.
“started to go bad in April 2026...coil issue...cost $400 to fix” — luckylist13 homeowner, 2026-07-01
AO SMITH Faulty Hybrid hot water heaters · HeatingHelp — The Wall · 2026-07-01 · read it in context
Same platform, second owner: reports a second replacement unit, still under two years old, already showing the recurring ECC error code, and argues A.O. Smith should refund rather than keep swapping units. Filed against the shared Voltex AL platform, so treated as applying to both the 66- and 80-gallon capacity variants.
“Im on my second heater and its less than 2 years old and its already displaying the ECC error code.” — RIRED homeowner, 2024-02-01
Reported for A. O. Smith ProLine XE Voltex AL (HPTS-80) Heat Pump Water Heater, 80 gal, not this exact model — included here because it's the same family and counts toward the totals above.
AO SMITH Faulty Hybrid hot water heaters · HeatingHelp — The Wall · 2026-07-01 · read it in context
A GBA 'Expert Member' commenting on the same June 2024 thread described his own A. O. Smith heat pump water heater: the compressor failed within 6 months of installation (replaced under warranty), then about 12 months after that a heating element shorted and tripped the breaker; he replaced both elements himself and says it has worked since. No tank size or model number given, so filed at the category level rather than pinned to a specific SKU (the catalog carries this line as the ProLine XE Voltex AL HPTS-66/HPTS-80).
“I have an AO Smith. I first installed it about two years ago, the compressor failed within six months and was replaced under warranty. Twelve months after that the circuit breaker started tripping, one of the heat elements had shorted out.” — DCcontrarian homeowner, 2024-06-02
Reported on the ProLine XE Voltex AL line; size not stated — included here because it's the same family and counts toward the totals above.
Heat Pump Water Heater inadequate – looking for solutions · GreenBuildingAdvisor Q&A · 2024-06-02 · read it in context
Parts and service availability
Whether a technician can get parts and knows the equipment. Consistently the largest gap between brands, and absent from every spec sheet.
Thin evidence — too few independent reports to call this a pattern. Shown because it may still be worth asking your contractor about.
Trade view is that local service coverage matters more than the efficiency difference between these two brands. Both are competent products; the deciding factor is who can actually service it near you.
“It could boil down to who has better service in your area” — Larry Weingarten trade, 2021-01-15
Heat Pump Water Heater — A.O. Smith vs Rheem? · HeatingHelp — The Wall · 2021-01-15 · read it in context
Warranty and manufacturer support
What actually happens when owners make a claim.
Thin evidence — too few independent reports to call this a pattern. Shown because it may still be worth asking your contractor about.
Specific trade warning to read water heater warranties closely and avoid pro-rated terms, which reduce in value over the life of the unit rather than paying out in full.
“read the warranties closely… some are pro-rated, like tires, which I don't like to see” — Larry Weingarten trade, 2021-01-15
Heat Pump Water Heater — A.O. Smith vs Rheem? · HeatingHelp — The Wall · 2021-01-15 · read it in context
Sources are linked so you can verify any of this yourself. We don't mirror content — Amazon in particular permits no republication of review text, so where we use retailer data we show the aggregate rating and link out. How we collect and weight this →
Compare against
A. O. Smith ProLine XE Voltex AL (HPTS-80) Heat Pump Water Heater, 80 gal
80-gallon version of the same ProLine XE Voltex AL 'Smart Hybrid' platform as the HPTS-66 — same compressor and control architecture, larger tank.
GE Profile GeoSpring Smart Hybrid Heat Pump Water Heater, 50 gal
GE's flagship heat pump water heater, relaunched under the Profile line with FlexCAPACITY mixing and Wi-Fi control. ENERGY STAR-certified at UEF 4.50 -- the highest efficiency figure in this catalogue at any size.
GE Profile GeoSpring Smart Hybrid Heat Pump Water Heater, 80 gal
80-gallon version of the same Profile GeoSpring Smart Hybrid platform as the 50-gallon model -- same UEF 4.50, larger first-hour rating.
Rheem ProTerra Hybrid Heat Pump Water Heater, 50 gal
The default heat pump water heater for most US households: 50 gallons, UEF 3.75, widely stocked and widely serviced.
Before you buy this
Ask for the first-hour rating, not just tank size, and check it against your household's simultaneous demand — showers and laundry at the same time — rather than headcount alone. If it's a heat pump water heater, confirm the room has enough air volume (or a duct kit) that it won't spend winter on resistance backup, and that there's a real route for condensate, not just a nearby floor drain. Confirm the panel has spare 240V capacity. And if you're removing a gas unit that shared a flue with a furnace, ask what happens to that flue once your water heater's draft is gone — an orphaned flue can backdraft.