Air Compressors
Chain Saws
Electric Generators
Lawn Mowers
Leaf Blowers
Pressure Washers
Snow Blowers
Sump Pumps
Water Pumps
More▶

✖

Free Shipping On Orders Over $199

Welcome: Sign In | Contact UsMy Account | Log Off

My Cart :

Preferred Customer

New Customers

E-Mail Address

First Name

Last Name

Password

Verify Password

Returning Customers

E-Mail Address

Password

Forgot Your Password?

Call Us: (855)-436-0140

Shop By Category
- Cooling
- Heating
- Ventilation
  - Fans
    Whole House Fans
    Inline Duct Fans
    Exterior Duct Fans
    Bathroom Fans
    Dryer Boosters
    Exhaust Fans
    Popular Brands
    Panasonic
    Fantech
    Soler & Palau
    QuietCool
    Air King
  - Air Exchangers
    Air Exchangers
    Popular Brands
    Fantech
  - Energy Recovery Ventilators
    Side Port
    Top Port
    Residential
    Commerical
    Popular Brands
    Clean Comfort
    Mitsubishi
    Fantech
    Panasonic
    Soler & Palau
    Goodman
  - Heat Recovery Ventilators
    Side Port
    Top Port
    Residential
    Commerical
    Popular Brands
    Clean Comfort
    Goodman
    Fantech
  - Ventilation Accs
    Indoor Air Quality Accessories
    Fan Ducting Materials
    Fan Controls
    Fan Dampers
    Fan Grilles
    Fan Housings
    Popular Brands
    Mitsubishi
    Fantech
    Clean Comfort
    Aprilaire
    Nest
  - Make-Up Air
    Make-Up Air Systems
    Make-Up Air Heaters
    Popular Brands
    Electro
    Fantech
  - Air Curtains
    Air Curtains
    Popular Brands
    Williams
  - Range Hoods
    Air King
    Popular Brands
    Air King
- Air Quality
  - Air Purification
    Media Air Cleaners
    Electronic Air Cleaners
    UV Air Purifiers
    Accessories
    Popular Brands
    Aprilaire
    Clean Comfort
    Emerson
    Fantech
    Goodman
    White Rodgers
  - Air Exchangers
    Air Exchangers
    Popular Brands
    Fantech
  - Energy Recovery Ventilators
    Side Port
    Top Port
    Residential
    Commercial
    Popular Brands
    Aprilaire
    Clean Comfort
    Fantech
    Goodman
    Mitsubishi
    Soler & Palau
  - Heat Recovery Ventilators
    Side Port
    Top Port
    Residential
    Commercial
    Popular Brands
    Clean Comfort
    Fantech
    Goodman
  - Dehumidifiers
    Stand Alone
    Ducted
    Accessories
    Popular Brands
    Aprilaire
    Clean Comfort
  - Humidifiers
    Evaporative
    Steam
    Accessories
    Popular Brands
    Aprilaire
    Clean Comfort
    Goodman
  - I.A.Q Parts & Accessories
    ERV/HRV Accessories
    Air Purification Accessories
    Humidifier Accessories
    Dehumidifier Accessories
    Smoke & Carbon Monoxide Detectors
    Popular Brands
    Aprilaire
    BestAir Pro
    Clean Comfort
    Fantech
    Goodman
    Nest
  - Filters
    95% DOP & HEPA/UPLA Filters
    Air Filter Media & Auto Rolls
    Disposable Industrial Grade Filters
    Manufacturer Specific Filters
    Medium/High Efficiency Rigid Filters
    Metal Washable Air & Grease Filters
    Popular Brands
    Ameristar
    BestAir Pro
    Clean Comfort
    Flanders
    White Rodgers
  - Fans
    Whole House Fans
    Inline Duct Fans
    Exterior Duct Fans
    Bathroom Fans
    Dryer Boosters
    Exhaust Fans
    Popular Brands
    Fantech
    Panasonic
    Soler & Palau
    White Rodgers
    QuietCool
- Water Heaters
  - Tankless Water Heaters
    Gas
    Electric
    Popular Brands
    Noritz
    Rinnai
    A.O. Smith
    Bosch
    Eemax
    Takagi
  - Indirect Water Heaters
    20 - 40 Gal
    40 - 60 Gal
    60 - 80 Gal
    80 - 100 Gal
    100 - 120 Gal
    Popular Brands
    Amtrol
    Buderus
    Burnham
    Crown Boiler
    Dunkirk
    Laars
    Peerless
  - Domestic Hot Water Expansion Tanks
    Water Hammer Arrestors
    Expansion Tanks
    Popular Brands
    Amtrol
  - Hot Water Storage Tanks
    Hot Water Storage Tanks
    Popular Brands
    Amtrol
    Dunkirk
  - Recirculating Pumps & Controls
    Recirculating Pumps
    Fittings
    Timers & Aquastats
    Demand Controls
    Popular Brands
    Grundfos
    Taco
  - Solar Hot Water Heaters
    Kits
    Collectors
    Storage Tanks
    Accessories
    Popular Brands
    Caleffi
    Bosch
    Taco
    Amtrol
    Dunkirk
    Buderus
  - Water Heater Parts & Accessories
    Fittings
    Venting Materials
    Controls
    Water Quality Accessories
    Mounting Materials
    Freeze Protection Accessories
    Popular Brands
    Noritz
    Rinnai
    Dunkirk
    White Rodgers
    Triangle Tube
    Crown Boiler
    Taco
  - Tank Water Heaters
    Natural Gas(NG)
    Electric
    Popular Brands
    A.O. Smith
- Shower & Tile
- Thermostats & Controls
  - Thermostats
    Smart Thermostats
    Wi-Fi Thermostats
    Programmable Thermostats
    7-Day Programmable Thermostats
    Popular Brands
    Aprilaire
    Ecobee
    Emerson
    Honeywell
    Nest
    White Rodgers
  - Central Air Controls
    Gas Valves
    Ignition Controls
    Warm Air Controls
    Zone Controllers
    Popular Brands
    White Rodgers
  - Boiler Controls
    Aquastats
    Boiler Control Accessories
    Reset Controls
    Staging & Modulating Controls
    Popular Brands
    Buderus
    Hydrolevel
    Taco
    Tekmar
    Weil-McLain
    White Rodgers
  - Control Accessories
    Relays
    Transformers
    HVAC Control Sensors & Accessories
    Popular Brands
    Aprilaire
    Ecobee
    Emerson
    Goodman
    Taco
    Weil-McLain
    White Rodgers
- Small Appliances
  - Wine Coolers
    Up to 29 Bottles
    30 – 59 Bottles
    60+ Bottles
    Built-In
    Free Standing
    Popular Brands
    Avallon
    Edgestar
    Koldfront
  - Kegerators
    Single Tap
    Dual Tap
    Triple Tap
    Built-In
    Free Standing
    Popular Brands
    Edgestar
- HVAC Tools
Shop By Brand

View All
Brands
Buying Guides

Shop By Category + −
- Cooling + −
  - Mini Split Systems (Ductless) + −
    Heat Pump Systems
    Cooling Only Systems
    Mini Split Components
    Mini Split Accessories
  - Central Air Conditioners + −
    A/C Condensers
    Air Handlers & Coils
    Packaged Units
    Central A/C Accessories
  - Central Air Kits + −
    A/C & Furnace Kits
    Furnace & Heat Pump Kits
    A/C & Air Handler Kit
    Heat Pump & Air Handler Kits
    A/C & Coil Kits
  - Room Air Conditioners + −
    Portable Air Conditioners
    Through-the-Wall Air Conditioners
    Window Air Conditioners
    Mini Split Systems (Ductless)
    PTAC Units
    Evaporative Coolers
  - Cooling Controls + −
    Thermostats
    Zone Controllers
    Zone Dampers
    By-Pass Dampers
    Damper Accessories
  - PTAC Units + −
    Cooling & Electric Heat Units
    Heat Pump & Electric Heat Units
    PTAC Accessories
  - Central Heat Pumps + −
    Single-Stage Heat Pumps
    Two-Stage Heat Pumps
    Air Handlers & Coils
    Packaged Heat Pumps
    Packaged Heat Pump & Furnace
  - Hydronic Cooling + −
    Hydronic Air Handlers
    Chilled Water Coils
    Terminal Fan Coil Accessories
    Whole House Air Handler Accessories
    Whole House Air Handler Drive Components
- Heating + −
  - Boilers + −
    Electric Boilers
    Gas Boilers
    Oil Boilers
    Combi Boilers
  - Boiler Accessories + −
    Boiler Controls
    Boiler Trim
    Heat Exchangers
    Zoning & Circulation
  - Radiators + −
    Baseboard Radiators
    Panel Radiators
    Towel Warmers
    Parts & Accessories
  - Furnaces + −
    Gas Furnaces
    Electric Furnaces
    Furnace & A/C Kits
    Furnace & Heat Pump Kits
    Packaged Furnace & A/C
    Packaged Furnace & Heat Pump
  - Heat Pumps + −
    Central Heat Pumps
    Mini Split Heat Pumps
    PTAC Heat Pumps
    Heat Pump & Furnace Kits
    Packaged Heat Pumps
    Packaged Heat Pump & Furnace
  - Radiant Heating + −
    Electric Floor Heating
    Electric Snow Melting
    Radiant Tubing
    Radiant Tubing Accessories
  - Unit Heaters + −
    Gas Fired Unit Heaters
    Hot Water/Steam Unit Heaters
    Electric Unit Heaters
    Oil Fired Unit Heaters
    Unit Heater Accessories
  - Infrared Heaters + −
    Infrared Tube Heaters
    High Intensity Infrared Heaters
    Patio Heaters
    Patio Heater Components
    Infrared Heater Accessories
  - Heating Controls + −
    Gas Valves
    Thermostats
    Zone Controllers
    Ignitors
    Ignition Controls
    Thermocouples
  - Hydro-Air + −
    Hydronic Air Handlers
    Hot Water Coils
    Terminal Fan Coil Accessories
    Air Handler Accessories
    Air Handler Drive Components
  - Electric Warm Air + −
    Plenum Heaters
    Duct Heaters
    Electric Furnaces
    Electric Heat Controls
  - Mini Split Heat Pumps + −
    Heat Pump Systems
    Heat Pump Components
    Mini Split Accessories
- Ventilation + −
  - Fans + −
    Whole House Fans
    Inline Duct Fans
    Exterior Duct Fans
    Bathroom Fans
    Dryer Boosters
    Exhaust Fans
  - Air Exchangers + −
    Air Exchangers
  - Energy Recovery Ventilators + −
    Side Port
    Top Port
    Residential
    Commerical
  - Heat Recovery Ventilators + −
    Side Port
    Top Port
    Residential
    Commerical
  - Ventilation Accs + −
    Indoor Air Quality Accessories
    Fan Ducting Materials
    Fan Controls
    Fan Dampers
    Fan Grilles
    Fan Housings
  - Make-Up Air + −
    Make-Up Air Systems
    Make-Up Air Heaters
  - Air Curtains + −
    Air Curtains
  - Range Hoods + −
    Air King
- Air Quality + −
  - Air Purification + −
    Media Air Cleaners
    Electronic Air Cleaners
    UV Air Purifiers
    Accessories
  - Air Exchangers + −
    Air Exchangers
  - Energy Recovery Ventilators + −
    Side Port
    Top Port
    Residential
    Commercial
  - Heat Recovery Ventilators + −
    Side Port
    Top Port
    Residential
    Commercial
  - Dehumidifiers + −
    Stand Alone
    Ducted
    Accessories
  - Humidifiers + −
    Evaporative
    Steam
    Accessories
  - I.A.Q Parts & Accessories + −
    ERV/HRV Accessories
    Air Purification Accessories
    Humidifier Accessories
    Dehumidifier Accessories
    Smoke & Carbon Monoxide Detectors
  - Filters + −
    95% DOP & HEPA/UPLA Filters
    Air Filter Media & Auto Rolls
    Disposable Industrial Grade Filters
    Manufacturer Specific Filters
    Medium/High Efficiency Rigid Filters
    Metal Washable Air & Grease Filters
  - Fans + −
    Whole House Fans
    Inline Duct Fans
    Exterior Duct Fans
    Bathroom Fans
    Dryer Boosters
    Exhaust Fans
- Water Heaters + −
  - Tankless Water Heaters + −
    Gas
    Electric
  - Indirect Water Heaters + −
    20 - 40 Gal
    40 - 60 Gal
    60 - 80 Gal
    80 - 100 Gal
    100 - 120 Gal
  - Domestic Hot Water Expansion Tanks + −
    Water Hammer Arrestors
    Expansion Tanks
  - Hot Water Storage Tanks + −
    Hot Water Storage Tanks
  - Recirculating Pumps & Controls + −
    Recirculating Pumps
    Fittings
    Timers & Aquastats
    Demand Controls
  - Solar Hot Water Heaters + −
    Kits
    Collectors
    Storage Tanks
    Accessories
  - Water Heater Parts & Accessories + −
    Fittings
    Venting Materials
    Controls
    Water Quality Accessories
    Mounting Materials
    Freeze Protection Accessories
  - Tank Water Heaters + −
    Natural Gas(NG)
    Electric
- Shower & Tile + −
  - Shower Systems + −
    Complete Shower Kits
    Linear Drain Shower Systems
    Drain Bodies
    Grates
    Shower Profiles
    Shower Trays
  - Towel Warmers + −
    Hot Water Towel Warmers
    Electric Towel Warmers
    Hooks & Bars
    Electric Towel Warmer Controls
  - Bath & Shower Components + −
    Drain Kits
    Drain Grates
    Shower Niches
    Shower Benches
    Shower Bases & Pans
    Shower Building Panels
  - Domestic Hot Water Expansion Tanks + −
    Water Hammer Arrestors
    Water Heater Expansion Tanks
    Hot Water Storage Tanks
  - Tile Profiles + −
    Balcony & Terrace Edging
    Barrier-Free Shower Profiles
    Wall & Countertop Edge Protection
    Floor Edge Protection & Transition
    Movement Joints & Cove Shaped Profiles
    Stair Nosing Profiles
  - Waterproofing Systems + −
    Waterproofing Membranes
    Uncoupling Membranes
    Waterproofing Accessories
    Sealants & Compounds
    Waterproofing Tools
  - Tile Floor Heating + −
    Electric Floor Heating Cable
    Electric Floor Heating Mats
    Electric Floor Heating Kits
    Electric Floor Heating Accessories
  - Bathroom Fans + −
    Ceiling Mount
    Inline Mount
    Wall Mount
- Thermostats & Controls + −
  - Thermostats + −
    Smart Thermostats
    Wi-Fi Thermostats
    Programmable Thermostats
    7-Day Programmable Thermostats
  - Central Air Controls + −
    Gas Valves
    Ignition Controls
    Warm Air Controls
    Zone Controllers
  - Boiler Controls + −
    Aquastats
    Boiler Control Accessories
    Reset Controls
    Staging & Modulating Controls
  - Control Accessories + −
    Relays
    Transformers
    HVAC Control Sensors & Accessories
- Small Appliances + −
  - Wine Coolers + −
    Up to 29 Bottles
    30 – 59 Bottles
    60+ Bottles
    Built-In
    Free Standing
  - Kegerators + −
    Single Tap
    Dual Tap
    Triple Tap
    Built-In
    Free Standing
- HVAC Tools + −
  - Hand Tools + −
    Screwdrivers
    Pliers
    Wrenches
    Hand Seamer & Notching Tools
    Nippers & Snips
    Tool Tags & Boxes
  - Refrigerant Management + −
    Charging Scales
    Recovery Tanks
    Refrigerant Recovery Machines
    Vacuum Pumps
    Vacuum Gauges
    Manifolds & Hoses
  - Testing Instruments + −
    Clamp Meters
    Multimeters
    Thermometers
    Thermal Cameras
  - Specialty Tools + −
    Flaring Tools
    Tubing & Soldering
    Thermal Cameras
Shop By Brand + −

View All
Brands
Buying Guides + −
- Cooling + −
  
  Mini Split Buying Guide
  
  Central Air Conditioner Buying Guide
  
  Mini Split Sizing Calculator
- Heating + −
  
  Furnace Buying Guide
  
  Boiler Buying Guide
  
  Unit Heater Buying Guide
- Ventilation + −
  
  How do ERV's and HRV's Work?
  
  Ventilation Solutions
  
  Finding a Dryer Booster
- Air Quality + −
  
  Choosing Right Air Filter
  
  Air Filter Overview
  
  Ventilation Solutions
- Water Heaters + −
  
  Which Water Heater is Right for You?
  
  Intro to Indirect Water Heaters
  
  Tankless Water Heater Buying Guide
- Shower & Tile + −
  
  Building a Shower Made Easy
  
  How to Build your Dream Shower
  
  Towel Warmer Buying Guide
- Thermostats & Controls + −
  
  Thermostat Buying Guide
  
  Ecobee3 Spotlight
  
  Intro to tekmar Boiler Controls

Home » Tankless Water Heaters » Ultra Low NOx Tankless Water Heaters

Quick Search

Select Product Type Inactive Dropdown Menu - Select Product Type In Above Menu Inactive Dropdown Menu - Select Product Type In Above Menu Inactive Dropdown Menu - Select Product Type In Above Menu Inactive Dropdown Menu - Select Product Type In Above Menu

Buy your Ultra Low Emissions Tankless Water Heater today and save.

Ultra Low NOx Tankless Water Heaters

Filter ▼

Filters:

Sort By:

Filter Results

Brand

A.O. Smith (23)

Bosch Thermotechnology (4)

Noritz (60)

Rinnai (66)

Takagi (28)

Price

500 - 699 (14)

700 - 899 (28)

900 - 1099 (35)

1100 - 1299 (46)

1300 - 1499 (26)

1500 - 1699 (17)

1700 - 1899 (2)

1900 - 2099 (11)

2100 - 2299 (1)

3500 - 3699 (1)

Maximum Input Capacity (BTU)

The Maximum Input Capacity describes how quickly the appliance will use fuel when delivering it's maximum capacity. The units may change depending on the fuel being used.

120000 - 139999 (24)

140000 - 159999 (13)

160000 - 179999 (23)

180000 - 199999 (119)

380000+ (1)

Energy Factor

Energy Factor (EF) is a measurement of water heater energy efficiency. The higher the energy factor, the more efficient the water heater. Learn More

0.93 (1)

0.95 (2)

AFUE (%)

AFUE (Annual Fuel Utilization Efficiency) measures the efficiency of combustion equipment over the entire heating season, and is calculated by dividing the amount of energy that is actually heating your home by the total energy contained in the fuel used by the boiler/furnace. Learn More

82 (1)

84 (1)

88 (2)

95 (1)

97 (2)

Efficiency (%)

84 (1)

97 (8)

Vent Type

Products that use combustion (burning) of fuel to create heat also create potentially dangerous gasses that need to be exhausted (AKA "Vented"). Depending on the product, venting can be done via a chimney, through a side wall, or use a second vent to provide fresh air to the appliance.

Common Direct Vent (2)

Concentric Vent (7)

Direct Vent (89)

Outdoor (No Venting) (79)

Power Vent (3)

Fuel Type

To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.

Liquid Propane (82)

Natural Gas (98)

Flow Rate at 40F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

4 (1)

5 (21)

6 (19)

7 (37)

8 (51)

9 (49)

10 (1)

Flow Rate at 50F Temperature Rise (GPM)

Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More

3 (3)

4 (22)

5 (15)

6 (87)

7 (51)

8 (1)

Compare

Noritz NCC1991 - 6.2 GPM at 60° F Rise - 94% Eff. - Gas Tankless Water Heater - Direct Vent (Scratch & Dent) EnergyStar Commercial Water Heater. Ultra Low NOx Emissions (SCAQMD Rule 1146.2 Compliant). Ratings: 9.3 GPM at 40° F Rise, 7.4 GPM at 50° F Rise, 6.2 GPM at 60° F Rise, 5.3 GPM at 70° F Rise. 188k Effective BTU/h.