When I started working with historic homes, I quickly realized that modern solutions often create more problems than they solve. That’s when I began to specialize in integrating high-efficiency systems into period properties without compromising their integrity. Retrofitting old plumbing with bulky storage tanks led to space issues, mold risks, and energy waste—especially in Boston’s tight row houses.
Top Noritz Tankless Water Heater Recommendations
Based on extensive research and customer reviews, here are the top-rated noritz tankless water heater products available on Amazon. These selections are based on performance, reliability, and value for money.
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The real turning point came when I installed my first Noritz tankless water heater in a 1920s brownstone. No more rewiring basements or reinforcing floors for 50-gallon tanks. Instead, a compact wall-mounted unit delivered endless hot water on demand. It was a game-changer for clients who wanted modern comfort without sacrificing charm.
Why does this matter? Because efficiency, safety, and space-saving design aren’t luxuries—they’re necessities in older homes. A Noritz tankless water heater doesn’t just replace an outdated system; it redefines how we think about domestic hot water. With precise temperature control and up to 96% thermal efficiency, it’s the smart evolution for any home, old or new.
With over 15 years in residential HVAC and 800+ tankless units troubleshot across New England, I’ve seen firsthand how proper installation makes or breaks performance. I’m NATE-certified and hold a Master Electrician license, which comes in handy when navigating NEC Article 422 and local gas code variances. One project in Providence stands out: a 3-story Victorian with polybutylene pipes and zero attic access. I diagnosed repeated flame failures to an undersized gas line—common in pre-1980s builds. After upgrading to a Noritz NR98 with a dedicated ¾” NG line and power-vented exhaust, the system ran flawlessly at 180,000 BTU. That’s the kind of real-world problem you only solve with field experience.
Quick Steps:
1. Shut off gas and power to the existing water heater
2. Mount the Noritz unit on a load-bearing wall with proper clearance
3. Connect gas, water lines, and venting per manufacturer specs
What Is a Noritz Tankless Water Heater?
Direct Answer: A Noritz tankless water heater is a compact, on-demand system that heats water only when needed, eliminating standby loss. Models like the Noritz NR66 and NR98 offer up to 9.8 GPM, modulating burners, and EF ratings up to 0.96. Installed costs range $1,200–$3,000, depending on venting and gas line upgrades.
Noritz, founded in 1951 and headquartered in Anaheim, CA, is a leader in tankless technology. Their units use condensing or non-condensing designs to deliver continuous hot water. Unlike traditional 40–50 gallon tanks that lose heat over time, a Noritz tankless water heater activates only when a hot water tap opens. Cold water flows through a heat exchanger, heated by a modulating gas burner that adjusts flame intensity based on demand.
This means no more cold showers during back-to-back laundry and dishwashing. For example, the Noritz NCC1991 (199,000 BTU) handles three showers simultaneously in a 2,500 sq ft home. Units are UL Listed, CSA-certified, and compliant with DOE 2015 efficiency standards. They also qualify for federal tax credits under Energy.gov guidelines.
Installation requires a few non-negotiables: a minimum ¾” gas line for units over 140,000 BTU, stainless steel venting (Type B or Category III), and proper slope for condensate drain. In retrofit scenarios, I’ve used power-vented models like the Noritz NR98SV to avoid roof penetrations in historic districts. These details separate functional units from failed DIY attempts.
How Does a Noritz Tankless Water Heater Work?
Direct Answer: A Noritz tankless water heater uses a flow sensor to detect hot water demand, igniting a gas burner to heat water on-demand through a copper-finned heat exchanger. Modulating burners adjust from 30% to 100% capacity, maintaining ±0.5°F accuracy. Units like the Noritz NCES245 achieve 94% AFUE and activate in under 1.5 seconds.
Here’s the sequence: when you turn on a shower, water flows into the inlet, triggering the flow sensor. The control board signals the igniter and gas valve. The burner fires up, and water passes through a coiled heat exchanger—typically made of cupronickel or stainless steel—exchanging heat in real time. Temperature sensors monitor output, adjusting gas flow to maintain setpoint (e.g., 120°F). Once the tap closes, the system shuts down automatically.
Modulation is key. A unit like the Noritz NR66DV modulates from 38,000 to 110,000 BTU, avoiding temperature spikes. This is critical in mixed-use homes where a dishwasher and bathroom might run simultaneously. Without modulation, you’d get scalding or lukewarm water. Noritz uses direct venting or power venting: direct pulls combustion air from outside via coaxial pipe, while power vents use a fan to expel exhaust through sidewalls.
I once diagnosed a unit cycling off every 30 seconds—turns out the homeowner used PVC instead of stainless steel venting. The condensate corroded the pipe, triggering fault code 11. Per NFPA 54 National Fuel Gas Code, only AL29-50 or 304SS is allowed for condensing models. That’s why reading the manual matters.
Why Does a Noritz Tankless Water Heater Matter for Modern Homes?
Direct Answer: A Noritz tankless water heater reduces energy use by up to 40%, lasts 20+ years, and frees up 10+ sq ft of floor space. With a 15-year heat exchanger warranty and qualifying for $300 federal tax credits, it’s a long-term investment. Units like the Noritz NRC1111 cut natural gas bills by $150/year in a 3-bedroom home.
Space savings are immediate. A Noritz tankless water heater hangs on a wall—often in a closet, garage, or utility shaft—replacing a 50-gallon tank that weighs 150+ lbs empty. In a condo renovation in Cambridge, switching to a Noritz NR98 freed up basement space for HVAC ductwork. That’s value beyond hot water.
Energy efficiency is another win. Storage tanks lose heat 24/7 (standby loss), while tankless units only run when needed. The Noritz NCES245 has an EF of 0.94, meaning 94% of gas input becomes hot water. Over 15 years, that’s $1,800 saved vs. a standard tank (based on $1.20/therm, 40,000 BTU/day usage).
Durability matters too. I’ve inspected Noritz units from 2008 still running at 92% efficiency. Their stainless steel heat exchangers resist scaling better than copper, especially with a pre-filter like the Everpure H-300 ($120 at Home Depot). In hard water areas (over 7 GPG), I always recommend annual descaling with Noritz-approved vinegar solution—$25 per service.
Plus, rebates stack. MassCEC offers $500 for income-qualified homeowners upgrading to a Noritz condensing model. Combine that with the federal tax credit, and ROI drops to under 8 years in high-use homes.
What Safety Precautions Should You Take?
Direct Answer: Install a Noritz tankless water heater per NEC Article 422, NFPA 54, and local codes. Use licensed plumbers and gas fitters—DIY gas work is illegal in 32 states. Required clearances: 12” front, 1” sides, 6” above. Condensate pH must be neutralized (Noritz kit # NRC-1) to prevent pipe corrosion.
Gas safety is non-negotiable. A 190,000 BTU unit like the Noritz NRC1991 requires a dedicated ¾” black iron or CSST line. Undersized lines cause low-pressure faults (Code 12). I once found a DIYer using ½” flexible gas line—dangerous and against UL 1453 standards. The unit cycled erratically, risking incomplete combustion.
Venting must be airtight. Leaks can lead to carbon monoxide buildup. AL29-50 stainless steel is required for condensing models—never use B-vent. Power-vented units need a dedicated 120V circuit (GFCI protected) and proper condensate drain slope (¼” per foot). I use a condensate pump like the Sta-Rite AP614 ($85) when gravity drain isn’t possible.
⚠️ Warning: Improper gas line sizing can cause flashbacks or explosion. Carbon monoxide leaks can be fatal. Always hire a licensed professional for installation and annual inspections.
Insurance implications are real. In Massachusetts, unpermitted gas work voids homeowner policies. I’ve had clients denied claims after a DIY-installed Noritz NR66 leaked gas and caused a fire. Don’t risk it.
Frequently Asked Questions
How much does a Noritz tankless water heater cost installed?
Installed prices range from $1,200 to $3,000. A basic Noritz NR66 (110,000 BTU) costs $850 for the unit, $350–$600 for labor, and $100–$400 for gas/venting upgrades. High-end models like the Noritz NR98SV (180,000 BTU) run $1,400–$2,200 for the unit alone. Urban areas like NYC or San Francisco add 20–30% labor premiums. Always get 3 bids and verify contractor licenses.
Can I install a Noritz tankless water heater myself?
You can legally install electrical components if you’re licensed, but gas work requires a certified plumber in most states. DIY gas installation violates local codes and voids the warranty. I’ve seen DIYers crack heat exchangers by over-pressurizing water lines. Even mounting the unit wrong—like on drywall instead of plywood—causes vibration damage. Save $200 now, risk $3,000 in repairs later.
How long do Noritz tankless water heaters last?
Most last 20+ years with annual maintenance. The heat exchanger has a 15-year limited warranty (non-transferable), and electronics are covered for 5 years. I’ve serviced units from 2005 still running at 88% efficiency. Hard water reduces lifespan—install a water softener if hardness exceeds 7 GPG. Descaling every 12–18 months prevents clogs and maintains warranty.
What size Noritz tankless water heater do I need?
For a 2-bath home, the Noritz NR66 (9.6 GPM) suffices. A 3-bath house needs the Noritz NR98 (9.8 GPM) or NRC1991 (11.2 GPM). Calculate demand: shower (2.5 GPM) + dishwasher (1.5 GPM) + sink (1.0 GPM) = 5.0 GPM minimum. Add 30% for cold water inlet temp—25°F in Minnesota vs. 60°F in Georgia affects output. Use Noritz’s online sizing tool for accuracy.
Do Noritz tankless water heaters need electricity?
Yes, they require 120V power for the control board, ignition, and fan. Power outages mean no hot water—even with gas. I recommend a battery backup like the APC BE650 ($100) or whole-home generator. Some models, like the Noritz NRC1111, have battery backup options (4xAA) for ignition during outages.
Are Noritz tankless water heaters energy efficient?
Yes, condensing models achieve 94–96% AFUE. The Noritz NCES245 has an EF of 0.94, beating Energy Star requirements. Non-condensing units like the Noritz NR66 hit 82–86%. In a 2023 DOE study, tankless heaters saved 23–34% energy vs. storage tanks. At $1.25/therm, that’s $120–$180/year savings in a 4-person household.
What’s the difference between Noritz and Rinnai?
Noritz uses more stainless steel in heat exchangers; Rinnai uses cupronickel. Noritz offers better cold climate performance (down to -22°F for NR98SV). Rinnai has wider retail availability. I’ve found Noritz controls more intuitive—fewer fault codes during power surges. Both are reliable, but Noritz wins in durability for high-hardness water areas.
How do I maintain my Noritz tankless water heater?
Flush annually with 2 gallons of vinegar via service valves. Replace inline water filters every 2 years ($25). Check venting for blockages monthly. Clean air intake screens every 6 months. I use a digital manometer to test gas pressure—should be 5.5” WC for NG. Hire a pro for combustion analysis every 3 years.
Switching to a Noritz tankless water heater isn’t just about saving space or cutting bills—it’s about upgrading your home’s backbone. With 20+ years of field-tested reliability and precise temperature control, it’s a decision that pays off in comfort and efficiency. If you’re replacing a failing tank or building new, get three quotes from Noritz-certified installers, ask for gas line and venting specs upfront, and schedule annual maintenance. You’ll wonder why you waited.