Navien Water Heaters on Long Island

Water Heater Brand

About Navien Water Heaters

Domino Fuel is a Navien Service Specialist, and we install, repair and service Navien water heaters across Long Island. We've been family-owned since 1981, and we stock the common Navien parts so most repairs finish on the first visit.

Navien's water heaters come from KD Navien, a South Korean maker founded in 1978 that opened its North American arm in 2006. Navien's North American head office is in Irvine, California. The company says it was the top-selling maker of gas tankless water heaters and wall-hung boilers in North America in 2024.

Condensing gas equipment is its specialty. The water heater lineup covers condensing tankless (NPE-A2 and NPE-S2), non-condensing tankless (NPN and NHW) and, more recently, the NWP500 heat pump water heater.

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All Models Serviced

Model Lineup

Navien Water Heater Models We Install and Service

Series	Key Ratings	Good For
NPE-A2 (NPE-180A2, 210A2, 240A2)	Up to 0.95 UEF, up to 15:1 turndown, max input 150,000 to 199,900 BTU, ComfortFlow buffer tank and pump	Faster hot water at far taps without an extra pump
NPE-S2 (NPE-150S2 to 240S2)	Up to 0.96 UEF, up to 15:1 turndown, 120,000 to 199,900 BTU, 2 inch PVC up to 75 ft	Whole-house tankless without built-in recirculation
NHW-AI and NHW-AE (non-condensing)	Built-in recirculation pump and buffer tank, 3 by 5 inch metal concentric vent	Swapping out an older non-condensing tankless
NPN-U and NPN-E (non-condensing)	Compact, indoor or outdoor retrofit units	Simple replacements
NWP500 (heat pump, 50, 65, 80)	Up to 4.05 UEF, under 45 dBA, stainless tank with no anode, Wi-Fi built in	All-electric homes

Long Island Homes

Navien Water Heaters for Long Island Homes

If you're replacing a 40 or 50 gallon gas tank, keep in mind that a 199,900 BTU NPE needs a much bigger gas supply than the tank did, so we check meter and pipe sizing first. Navien rates the NPE for 1/2 inch gas pipe up to 24 feet, which helps in tight basements.

Big older homes often have long pipe runs. The NPE-A2's built-in pump can recirculate through a return line, or through your existing supply lines with Navien's optional NaviCirc valve. Hard water is common here, so we install service valves for flushing.

Oil-heat homes without gas can look at the NWP500. It needs at least 450 cubic feet of space for an unvented install and runs on air between 41°F and 113°F. PSEG Long Island pays up to $1,200 on qualifying ENERGY STAR heat pump water heaters in 2026, limited to one per account every 5 years.

Warranty

Navien Water Heater Warranty

For residential NPE-A2 and NPE-S2 units with standard or controlled recirculation, Navien covers the heat exchanger for 15 years, parts for 5 years and labor for 1 year. If an outside pump runs nonstop with no aquastat control, coverage drops to 5 years on the heat exchanger and 3 on parts.

Navien voids coverage for installs by non-licensed installers, and it excludes hard water and mineral build-up damage. Its combi-boiler warranties go further and void units bought online, so buy through a contractor. As a Navien Service Specialist, we contact Navien Technical Support when a warranty claim needs approval.

On top of the manufacturer's coverage, Domino backs every installation with a 1-year labor warranty.

Compare Brands

Navien vs Rinnai Water Heaters

Both build condensing tankless units with a 15-year residential heat exchanger warranty. Rinnai's SENSEI RX lists up to 0.98 UEF; Navien's NPE-S2 lists up to 0.96. Rinnai caps its heat exchanger coverage at 12,000 operating hours, while Navien ties its terms to how your recirculation is controlled.

The bigger difference is how each handles recirculation and venting. Navien's NPE-A2 has a buffer tank as well as a pump, while Rinnai's RXP uses a built-in pump with Smart-Circ scheduling. Navien also lists 2 inch PVC up to 75 feet on the NPE-2. See all brands on our water heater brands page.

Repair & Service

Navien Water Heater Repair and Service

We stock common Navien parts, including inlet filters, flame rods, igniters and sensors. A yearly descaling flush and filter cleaning keeps an NPE running at its rated output. Book water heater repair any time, day or night.

Error code on the front panel: the unit is reporting ignition, flame, vent or water flow trouble.
Hot water fluctuates: scale in the heat exchanger, a dirty inlet filter or a gas supply that's too small.
ComfortFlow pump runs but no hot water at the tap: the recirculation settings or a check valve needs attention.
Condensate leaking: the drain or neutralizer is clogged.
NWP500 slow to recover: the room is too cold or the air filter needs cleaning.
Unit won't fire after a power surge: the control board or a fuse may need replacing.

Installation

Navien Water Heater Installation and Replacement

Your total depends on which NPE you choose, any gas meter or pipe upgrade, vent length, recirculation piping and hauling the old tank. Call for a quote, or read about switching on our tankless water heater page.

We count your bathrooms and fixtures and check winter water temperature to size the NPE.
We measure the gas line and meter and plan the PVC vent route.
You get a written quote naming the Navien model, with or without ComfortFlow.
We remove the old tank, mount the Navien on the wall, and install isolation valves, the condensate drain and vent.
We fire it, set the recirculation schedule, and test hot water at your farthest tap.

FAQ

Navien Water Heater FAQs

Common questions about this water heater brand on Long Island.

1What Is Navien ComfortFlow?

It's a buffer tank and recirculation pump built into the NPE-A2. Navien says it was the first to include both in a tankless water heater, so you don't need an external pump for recirculation.

2Is the NPE-A2 or NPE-S2 Better for My Home?

Pick the A2 if you wait a long time for hot water at far taps. Pick the S2 if your pipe runs are short, since Navien rates it slightly higher at up to 0.96 UEF.

3Does Navien Make a Heat Pump Water Heater?

Yes, the NWP500 in 50, 65 and 80 gallon models. Navien rates it up to 4.05 UEF with a stainless steel tank and no internal anode rod.

4Can I Buy a Navien Online and Have You Install It?

We can, but think twice. Navien's combi-boiler warranties void units bought online, and its tankless warranties require a licensed installer, so buying through a contractor protects your coverage.

5Is Domino Fuel a Navien Dealer?

Domino Fuel is a Navien Service Specialist. We install, repair and service Navien tankless and heat pump water heaters on Long Island.

Navien Water Heater Installation and Repair on Long Island