

199,000 BTU Non-Condensing tankless water heater for heavy residential or light commercial use.
The ATI-510U 200+ for indoor installation is perfect for heavy residential applications such as domestic recirculation systems or space heating, as well as commercial applications like small beauty salons and restaurants.
New, Improved Features
• Heat-resistant copper heat exchanger tubing
• Thicker heat exchanger drum
• Includes a pump control port
• Easy-Link System for up to 4 units
Specification highlights
• Set up for natural gas from the factory, but field convertible from NG to LP with included gas conversion kit
• 199,000 BTUs
• Maximum flow rate of 10.0 GPM
• Non-condensing technology
• Ultra-Low NOx emissions (natural gas only). Complies with SCAQMD Rule 1146.2 for NOx emissions requirement of 14 ng/J or 20 ppm
• Complies with lead-free standards
• Built-in freeze protection
• Indoor models include factory-installed 120V power cord with plug
• Overheat cutoff fuse
• Inlet and outlet thermistors for constant temperature monitoring
• Can be used for radiant/hydronic/space heating as well as the usual running hot water (domestic hot water/DHW). See page 36 of the installation manual (download below).
Optional Accessories
• Horizontal, through-wall or vertical stainless steel venting kit
• Recess Box (for outdoor models)
• Pipe Cover
• Isolation Valve Kit
• Backflow Preventer
• Concentric Termination Kits
Certifications
![]() |
![]() |
![]() |
![]() |
Specifications
|
|
Documentation
• Ultra-Low NOx Manual
• Spec Sheet
Frequently Asked Question ("FAQ")
Q1: What are the differences between the ATI-510-N (ATI-510-I-N) and the ATI-510U-N (ATI-510U-I-N)?
A1.1: The ATI-510U-N adds a 3" flue opening for fresh air for combustion intake. The ATI-510-N took in fresh air from the grill at the bottom front of the heater.
1.2. The ATI-510-U complies with Ultra Low-NOX standards.
1.3. The water connections at the bottom of the heater are in different locations. The gas connection remains at the far right side.