Noritz NR501-DV-NG Non-Condensing Tankless Water Heater
Noritz NR501-DV-NG Non-Condensing Tankless Water Heater Review
The Noritz NR501-DV-NG is a non-condensing tankless water heater. The "NR501" identifies 140K BTU output in Noritz's non-condensing line; "DV-NG" means direct-vent natural gas.
Specs: 140,000 BTU natural gas input, UEF 0.82 (non-condensing), 6.6 GPM at a 35°F rise, copper heat exchanger, Category III stainless B-vent venting. 12-year warranty on heat exchanger.
Non-condensing positioning is for retrofits reusing existing chimney access — saves $700-$1,200 in venting work versus condensing tankless retrofit. The trade-off is the lower UEF (0.82 vs 0.95 for condensing), worth about $50-$80/year in additional gas cost.
About $1,400 unit, $2,600 installed. Right buyer: retrofit replacing aging atmospheric gas tank with existing reusable B-vent chimney, where Noritz dealer presence is established in the local market.
- On-demand operation at 5 GPM — no standby heat loss; unlimited hot water if demand is within flow-rate capacity
- UEF 0.82 — above federal minimum EF 0.62; solid efficiency for a non-condensing gas unit
- 10-year warranty — solid above-average coverage for this class
- Requires dedicated 180K BTU gas supply line — undersized gas piping is the leading cause of flow-rate shortfalls