Navien NPE-240S2 vs Takagi T-H3-OS-N 1

The Navien NPE-240S2 is the more efficient unit: UEF 0.96 versus 0.95 — about 1% less energy for the same hot water. At national average rates that works out to about $255/year for the Navien NPE-240S2 against $258/year for the Takagi T-H3-OS-N 1 — a $3 annual difference.

Navien NPE-240S2 Takagi T-H3-OS-N 1
Uniform Energy Factor (UEF) 0.96 0.95
Fuel Natural Gas, Propane Natural Gas
Max flow rate 5.8 GPM 5.8 GPM
Draw pattern High High
Annual gas use (natural gas) 176 therms/yr 178 therms/yr
Gas input rate 199 kBTU/h 199 kBTU/h
Max current draw 5 A 5 A
Vent type Power Direct Vent Power Vent
Smart / connected capable No No
Minimum activation flow 1 GPM 1 GPM
Annual propane use 192.35 gal/yr 194.53 gal/yr
Vent size 2 3
Height 27 in 22 in
Width 17 in 18 in
Depth 13 in 11 in
ENERGY STAR certified Yes Yes

Frequently asked questions

Which costs less to run, the Navien NPE-240S2 or the Takagi T-H3-OS-N 1?

The Navien NPE-240S2: about $255/year versus $258/year for the Takagi T-H3-OS-N 1 at national average rates — a $3 annual difference.

Are the Navien NPE-240S2 and Takagi T-H3-OS-N 1 both ENERGY STAR certified?

Yes — every water heater in this database is drawn from the U.S. EPA ENERGY STAR certified water heater datasets.