Navien NHW700-199AE – Non-Condensing Tankless Water Heater – Outdoor, 199,000 BTU

The Navien NHW700-199AE is a high-capacity, non-condensing tankless water heater built for outdoor residential applications. Designed to operate efficiently in a variety of climates, it delivers up to 199,900 BTU per hour and supports a maximum flow rate of 9.5 gallons per minute at a 35°F rise. The unit is equipped with Navien’s patented NaviTech™ stainless steel heat exchanger and a stainless steel Low NOx burner for durability and cleaner combustion. With a Uniform Energy Factor (UEF) of 0.81, the NHW700-199AE offers energy-efficient performance in a compact footprint.

This model comes with a built-in recirculation pump and buffer tank, helping to reduce hot water wait times and eliminate cold water bursts during demand cycles. It includes a built-in control panel for temperature adjustment and diagnostics, and is factory-configured for natural gas with an optional field conversion kit for propane. Safety features such as a flame rod, APS, high-limit temperature switch, and vent installation detector are integrated for peace of mind. The unit installs outdoors with NaviVent™ 3″ x 5″ concentric venting and requires no additional venting accessories.

Features

• Outdoor installation design
• 199,900 BTU/h input
• UEF rating of 0.81
• 9.5 GPM at 35°F rise, 7.4 GPM at 45°F rise
• Patented NaviTech™ stainless steel heat exchanger
• Stainless steel Low NOx burner (20 ppm)
• Built-in recirculation pump and buffer tank
• Electronic ignition system
• Built-in control panel for temperature setting and diagnostics
• Factory set for natural gas, field convertible to propane
• Vents using NaviVent™ concentric 3″ x 5″ system
• Safety features: flame rod, air pressure sensor, vent installation detector, water temp high limit switch, power surge fuse

Applications

• Residential outdoor water heating
• Homes needing high hot water output with minimal indoor space use
• Systems requiring reduced hot water wait time
• Installations in areas with natural gas or propane fuel availability
• Regions requiring Low NOx emissions compliance

Exclusive NaviTech stainless steel heat exchanger
The NWH-A series non-condensing tankless water heaters feature a stainless steel heat exchanger to deliver unmatched durability and performance.

ComfortFlow built-in recirculation system
The patented ComfortFlow system is the first to include a buffer tank, recirculation pump and fine-tuned controls into a tankless water heater.

NHW-A built-in control panel
Allows you to adjust water temperature, operation status and troubleshooting.

Built-in Air Pressure Sensor (APS)
Monitors vent system for blockage, automatically compensates for range of vent lengths, helps maintain proper air/gas ratio during operation, and ensures consistent hot water output during changing conditions.

Patented NaviTech stainless steel gas burner
Designed and manufactured by Navien to burn gas at higher efficiency than other system on the market.

Recirculation control built into circuit board
Ensures proper system setup, and reduces the need for additional components, saving installation time and cost.

Built-in Water Adjustment Valve (WAV) & Mixing Valve
Control flow to maintain setpoint and stabilize water temperature during flow changes.