Navien NPE-240S2 High Efficiency Condensing Tankless Water Heater, 199,900 BTU, Indoor/Outdoor, NG/LP Convertible

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Navien NPE-240S2 High Efficiency Condensing Tankless Water Heater, 199,900 BTU, Indoor/Outdoor, NG/LP Convertible

Name: Navien NPE-240S2 High Efficiency Condensing Tankless Water Heater, 199,900 BTU, Indoor/Outdoor, NG/LP Convertible
Brand: Navien
SKU: NAVI-NPE-240S2-NG/LP
Price: 1987.50 USD
Availability: InStock

NavienSKU: NAVI-NPE-240S2-NG/LP

Price:

$1,987.50

Stock:

In stock (101 units), ready to be shipped

Quantity:

Ships UPS Ground for a flat $149 (continental US).
Flat rate by order weight: $119 under 70 lb · $149 for 70–100 lb · $189 for 100–150 lb.

Usually ships in 1–2 business days.

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Questions? Call (404) 678-9908 or chat with us.

Complete the install

Ships from Seattle, WA · 30-day returns · Manufacturer warranty

Shipping details

Shipping weight: 80.3 lb
Box size: 19.3 × 29.4 × 15.2 in

Heat Capacity (input) (Natural gas)	13,300 - 199,900 BTU/h
Heat Capacity (input) (Propane)	13,300 - 199,900 BTU/h
Efficiency ratings (UEF (NG & LP))	0.96
Flow rate (DHW) (35°F temp rise)	11.2 GPM
Flow rate (DHW) (45°F temp rise)	8.7 GPM
Flow rate (DHW) (67°F temp rise)	5.8 GPM
Minimum flow rate	0.5 GPM
Connection sizes (Cold water inlet)	3/4" NPT
Connection sizes (Hot water outlet size)	3/4" NPT
Connection sizes (Gas inlet)	3/4" NPT
Water pressure	15-150 PSI
Natural gas supply pressure (from source)	3.5 " WC to 10.5 " WC
Propane gas supply pressure (from source)	8 " WC to 13 " WC
Natural gas manifold pressure (min-max)	-0.03 " WC to -0.96 " WC
Propane gas manifold pressure (min-max)	-0.02 " WC to -0.96 " WC
Power supply (Main supply)	120V AC, 60 Hz
Power supply (Maximum power consumption)	200 W (max 2 A), 350 W (max 4 A) with external pump connected
Venting (Exhaust)	2" or 3" PVC, CPVC, approved polypropylene and stainless steel 2" or 3" special gas vent type BH (Class II, A /B/C)
Venting (Intake)	2" or 3" PVC, CPVC, approved polypropylene and stainless steel 2" or 3" special gas vent type BH (Class II, A /B/C)
Venting (Vent clearances)	0" to combustibles
High elevations	10,100 feet for both NG or LP gas. Please refer to Installation Manual for additional details and instructions.
Dimensions	17.3" W x 27.4" H x 13.2" D
Boiler weight	73 lbs
Materials (Casing)	Cold rolled carbon steel
Materials (Heat exchangers)	Primary heat exchanger: stainless steel Secondary heat exchanger: stainless steel
Safety Devices	Flame rod, APS, ignition operation detector, water temperature high limit switch, exhaust temperature high limit sensor, power surge fuse, burner high limit fuse, vent installation detector (VID)
AHRI number	206368362
Energy star certified	Yes
CSA	Yes
NSF (Standard 5)	Yes
Low Lead (<0.25%)	Yes
SCAQMD 1146.2 (NOx, <20ppm)	Yes

The Navien NPE-240S2 is a condensing tankless water heater from Navien's NPE-2 series. Same cabinet and the same pair of stainless steel heat exchangers as the NPE-240A2, without the internal pump — which is why it carries the higher efficiency rating of the two.

Rated input is 13,300 - 199,900 BTU/h on natural gas or propane — the unit is certified for both. It modulates from 199,900 BTU/h all the way down to 13,300, so it is not running at full fire to fill a sink.

How much hot water you actually get

Navien rates every tankless unit by temperature rise, because the colder the incoming water, the less of it one burner can heat. Here is what the NPE-240S2 delivers:

Temperature rise	Flow rate	Typical use
35°F	11.2 GPM	Warm-climate groundwater, or a preheated feed
45°F	8.7 GPM	The usual design point across most of the U.S.
67°F	5.8 GPM	Northern winter, incoming water near 40°F

Sized against a 2.5 GPM showerhead, the 67°F column is worth roughly 2 showers at once on the coldest day of the year, and more than that the rest of the year. Size to the 67°F row if your winter groundwater runs cold.

Minimum activation flow is 0.5 GPM, so it fires for a hand wash, not just a full shower.

Installing it

Cabinet: 17.3" W x 27.4" H x 13.2" D
Weight: 73 lbs
Water connections: 3/4" NPT cold in, 3/4" NPT hot out
Gas connection: 3/4" NPT
Water pressure range: 15-150 PSI
Power: 120V AC, 60 Hz
Venting: 2" or 3" PVC, CPVC, polypropylene or stainless steel, intake and exhaust
Vent clearance: 0" to combustibles
Altitude: approved to 10,100 feet for both NG or LP gas. See the installation manual for the details.
Heat exchanger: dual stainless steel, primary and secondary

Ratings and certifications

UEF: 0.96
ENERGY STAR® certified
CSA certified
NSF Standard 5
lead free (<0.25%)
SCAQMD 1146.2 low-NOx (under 20 ppm), the rule that governs Southern California
AHRI: 206368362

Model details

Brand: Navien
Manufacturer part number: NPE-240S2
UPC: 884954920894

Ships in the manufacturer's carton. Shipping is calculated at checkout by weight, dimensions and destination. Gas connection, venting and condensate disposal must be done by a licensed installer, to the Navien manual and to your local code.

Frequently asked questions

How many showers can the Navien NPE-240S2 run at once?

Navien rates the NPE-240S2 at 5.8 GPM at a 67°F temperature rise and 8.7 GPM at a 45°F rise. With 2.5 GPM showerheads that is roughly two showers at once on the coldest day of the year, and more the rest of the year.

Does the NPE-240S2 run on propane?

Yes. The unit is certified for both natural gas and propane, with a modulating input of 13,300 to 199,900 BTU/h.

What venting does the NPE-240S2 need?

Intake and exhaust run in 2" or 3" PVC, CPVC, polypropylene or stainless steel, with 0" clearance to combustibles. Gas, venting and condensate work must be done by a licensed installer to the Navien manual and local code.

What is the difference between the NPE-240S2 and the NPE-240A2?

They share the same cabinet and dual stainless steel heat exchangers. The NPE-240A2 adds an internal recirculation pump; the NPE-240S2 has no pump and carries the higher efficiency rating, 0.96 UEF.