Home Size Southern climate: 1+ bathrooms 
Indoor Unit Dimensions 20.5” (H) x 13.8” (W) x 6.7” (D)
Outdoor Unit Dimensions 20.5” (H) x 13.8” (W) x 6.7” (D)
Weight Indoor: 39 lbs., Outdoor: 36 lbs.
Gas Consumption
(NG & LP)
Max: 120,000 btuh
Min: 15,000 btuh
Capacity Range 0.5-6.6 Gal./min.
Energy Factor 0.91 (NG) 0.93 (LP)
Thermal Efficiency 93%
Temperature Settings 100-140°F (In 5°F intervals) (9 Options)
Accessories Remote controller & cord, Anchoring Screws


The ENERGY STAR rated NRC661, Noritz's newest efficient condensing model with a half inch gas line. Featuring the same energy-saving condensing technology as the rest of the Noritz eco-TOUGH™ Series of gas-fired residential tankless water heaters, the NRC661 has an Energy Factor of 0.91 for natural gas and 0.93 for LP. These ratings are nearly 10 points higher than that of a comparably sized, conventional tankless unit, and approximately 30 points higher than a standard, tank-type gas-fired water heater.

With a maximum input of 120,000 BTU per hour (BTUh), using a half-inch gas line up to 120 feet in length. A new, more accurate interpretation of the National Fuel Gas Code permits the use of the smaller-diameter gas piping for inputs up to 174,000 BTUh, as long as the water column pressure at the inlet of the unit is a minimum eight inches.

Key Features:
Super Efficient - DOE Energy Factor of 0.93
3" PVC Vent - Provides the highest efficiency, save time and money.
Digital Display - Assists in troubleshooting by indicating flow rates, temperature & common error codes. 
1/2" Gas Line - Cut installation times in half by not having to replace the existing gas line (Must ensure lines are sized correctly based on National Fuel Gas Code)
Tech Data Sheet Inside - Located inside the front cover, it gives the servicing contractor all necessary information needed to troubleshoot. 

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