Canada-wide gas boiler information · On-site service in Greater Vancouver, BC
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Comparison
Verdict in brief
The NRC661A-DV and NRC711-DV are the compact members of the NRC Series: both 0.89 UEF, indoor-only and sharing a 23.6 x 13.8 x 6.7 in cabinet, with the NRC711-DV firing to 157,000 BTU/h and 7.1 GPM against the NRC661A-DV's 120,000 BTU/h and 6.6 GPM, at 41 against 39 lb.
Published manufacturer figures. Input and output are kept separate; blanks mean the manufacturer did not publish that value.
| Specification | Noritz NRC661A-DV | Noritz NRC711-DV |
|---|---|---|
| Input, minimum | 15 MBH | 15 MBH |
| Input, maximum | 120 MBH | 157 MBH |
| Uniform Energy Factor (UEF) | 0.89 UEF | 0.89 UEF |
| Flow rate | 0.5 – 6.6 GPM | 0.5 – 7.1 GPM |
| Weight | 39 lb | 41 lb |
| Install location | Indoor only | Indoor only |
The NRC661A-DV and NRC711-DV are the small-chassis models in Noritz's NRC Series: indoor-only tankless water heaters at 0.89 UEF with a 15,000 BTU/h minimum fire and the same 23.6 x 13.8 x 6.7 in cabinet — noticeably smaller than the NRC98DV/NRC111DV pair.
The NRC711-DV steps up to 157,000 BTU/h of input against 120,000 and 7.1 GPM against 6.6, at 41 against 39 lb. Both share 0.5 GPM minimum flow, 115–140°F temperature settings and 120 VAC power, and both are DHW-only appliances with no space-heating circuit.
These compact units suit tight installations where the larger NRC chassis will not fit; the trade-off is capacity at the top of the range. The pages describe high-efficiency operation and print 0.89 UEF for both.
Noritz
The Noritz NRC661A-DV is a high-efficiency tankless water heater in the NRC Series — a DHW-only appliance, not a boiler — firing 15,000 to 120,000 BTU/h with 6.6 GPM maximum flow at 0.89 UEF.
Noritz
The Noritz NRC711-DV is a high-efficiency tankless water heater in the NRC Series — a DHW-only appliance, not a boiler — firing 15,000 to 157,000 BTU/h with 7.1 GPM maximum flow at 0.89 UEF.
Maximum input (120,000 against 157,000 BTU/h), maximum flow (6.6 against 7.1 GPM) and weight (39 against 41 lb). Both are 0.89 UEF with the same minimum fire and compact cabinet.
Footprint: the NRC661A/NRC711 cabinet is 23.6 x 13.8 x 6.7 in against the NRC98DV's 24.2 x 18.3 x 9.4 in. The larger model offers more capacity — 180,000 BTU/h and 9.8 GPM — where the space exists.
No. Both are compact residential tankless water heaters for domestic hot water only.
A consultation includes a heat-loss review so the size is right the first time.
On-site service in Greater Vancouver, BC. ROMA lists “Open 7 days” on its site; call to confirm same-day availability.
Sources and verification
Facts checked September 9, 2026. Last updated September 9, 2026. Technical reviewer: not yet assigned.