Takagi AT-D3U-IN - User Manual

Gas Tankless Water Heater
TM
Suitable for combination potable water heating
and space-heating
Please refer to local codes for space-heating compliance.
FEATURING
 • ENDLESSHOTWATER
 • ON-DEMANDUSAGE
 • COMPACT,SPACESAVING
 • ENERGYCONSERVATION
 • COMPUTERIZEDSAFETY
 • NOPILOTLIGHT
 • ComplieswithSCAQMDRule
1146.2forNOxemissionsrequire-
mentof14ng/Jor20ppm
 • FIELDGASCONVERTIBLE
 • EASY-LINKSYSTEMAND
MULTI-UNITSYSTEM
(510U (AT-D3U-IN/OS) only)
Ifyouhaveanyquestions,please
callorwriteto:
500TennesseeWaltzParkway
AshlandCity,TN37015
TollFree:1-877-737-2840
On-Demand Water Heater
Installation Manual and Owner’s Guide
- Do not store or use gasoline or other
flammablevaporsandliquidsinthevicinity
ofthisoranyotherappliance.
- WHATTODOIFYOUSMELLGAS
 • Donottrytolightanyappliance.
 • Donottouchanyelectricswitch,donot
useanyphoneinyourbuilding.
 • Immediatelycallyourgassupplierfrom
aneighbor'sphone.Followthegas
supplier'sinstructions.
 • Ifyoucannotreachyourgassupplier,call
thefiredepartment.
- Installation and service must be performed
byaqualifiedinstaller,serviceagencyorthe
gassupplier.
WARNING
If the information in these
instructions is not followed
exactly,afireorexplosionmay
resultcausingpropertydamage,
personalinjuryordeath.
ANSI Z21.10.3 ・ CSA 4.3
510U (AT-D3U-IN/OS)
only
Models
• 110U Outdoor (AT-KJr3U-OS)
• 310U Outdoor (AT-K5U-OS)
• 510U Outdoor (AT-D3U-OS)
• 110U Indoor (AT-KJr3U-IN)
• 310U Indoor (AT-K5U-IN)
• 510U Indoor (AT-D3U-IN)
Series 200

Takagi AT-D3U-IN Specifications

General

Brand	Takagi
Model	AT-D3U-IN
Category	Water Heater
Language	English

Summary

Product Specifications and Safety Guidelines

Manual Introduction and Models

Overview of the manual, water heater models, and core function.

Safety Guidelines

Critical safety information, definitions, and general precautions for installation and use.

Installation Guide

Clearances and Venting

Required physical clearances and essential venting instructions for safe installation.

High-Altitude and Installation Warnings

Prohibitions, warnings, and altitude adjustments for installation locations.

Gas, Water, and Electrical Connections

Guidelines for connecting gas supply, water lines, and electrical power.

System Configurations

Setup for remote controllers, Easy-Link, and Multi-Unit systems.

Operation and Maintenance

Initial and Normal Operation

Steps for safe startup, normal use, and controller functions.

Temperature and Flow Settings

Adjusting water temperature and understanding flow rate impact.

Freeze Protection and Maintenance

Features to prevent freezing and routine maintenance procedures.

Troubleshooting and Reference

Problem Diagnosis and Error Codes

Identifying and resolving common issues and interpreting error codes.

Components, Parts, and Warranty

Diagrams of components, parts list, performance charts, and warranty details.