Water heaters

Navien NPE-240A2 Condensing Tankless Water Heater

Navien NPE-240A2Wholesale contractor 50% data complete
$2,099 – $2,099
equipment only · 1 seller · seen 2026-08-16

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.

See the 1 listing this comes from →

Condensing gas tankless water heater, UEF 0.95, 11.2 GPM at a 35°F rise — Navien's mid-large residential model, ENERGY STAR certified.

Our take

On paper this beats the Rinnai RX160iN on UEF and roughly matches it on flow. What the spec sheet doesn't carry is the trade-side service reputation gap: a working plumber's own account of repeated gasket and O-ring repair calls on Navien units, against zero comparable calls for Rinnai over the same period. One credentialed source isn't a verdict, but it's the kind of thing worth asking your own installer about directly before choosing between the two.

Best for

Gas homes wanting the highest published UEF in the tankless class, installed by a shop that already knows the brand.

Watch out for

Sizing must be done on your winter groundwater temperature, not the national rating. See the field-reliability notes before assuming parts support will be as easy as Rinnai's.

What sellers are actually charging

The lowest in-stock, full-equipment price we've seen is $2,099, at SupplyStop.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.

SellerWhat you getPriceStockSeen
SupplyStop.com
online retailer
equipment system $2,099
$2,189
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.

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.

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.

negative
1 report · 1 from trade
19% evidence

Thin evidence — too few independent reports to call this a pattern. Shown because it may still be worth asking your contractor about.

A working master plumber reports Navien repair calls are dominated by worn gaskets and O-rings, in contrast to zero comparable repair calls he's fielded for the competing Rinnai line over the same period; also cites mineral scaling causing stuck check valves.

“I've been out to fix several Naviens, usually due to worn out gaskets and O-rings.” — Steven Smith trade, 2026-01-03

Navien NPE-240A2 Tankless Review · Independent trade-company blogs · 2026-01-03 · read it in context

Sizing and capacity in practice

Whether the unit as installed matches the load, including short-cycling and temperature overshoot from oversizing.

mixed
1 report
12% evidence

Thin evidence — too few independent reports to call this a pattern. Shown because it may still be worth asking your contractor about.

A newly installed Navien NPE-240A2 owner reported a shower running noticeably colder than their old tank heater, worsening further whenever a second fixture opened elsewhere in the house, at a measured flow of about 4.2 GPM. Forum members (including a plumbing professional) concluded the unit was likely being pushed to its maximum temperature-rise capability at that flow rate, and separately suggested the real cause might be a shower cartridge/temperature-limit-stop left set for the old tank's higher 150F setpoint rather than the tankless unit's 120F -- i.e., a sizing/setup issue more than a unit defect. One reply added a general caveat that tankless units 'may not be as reliable' as a tank when paired with continuous recirculation. The thread ends without the owner confirming which explanation was correct, so this is filed as a mixed-stance sizing/capacity signal rather than a clear-cut reliability claim.

“My issue is that shower in main bathroom seems to have colder water than when I had regular water heater. But more importantly, when someone turns on a faucet or another shower nearby, the water becomes even colder.” — GinoDivx homeowner, 2022-10-01

Navien NPE-240A2 - temperature fluctuations · HeatingHelp — The Wall · 2022-10-01 · 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

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.