A.O. Smith BTH 400 - User Manual

COMMERCIAL GAS WATER HEATERS
Instruction Manual
PRINTED 1216 100233746
PLACE THESE INSTRUCTIONS ADJACENT TO HEATER AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.
7KDQN\RXIRUEX\LQJWKLVHQHUJ\HI¿FLHQWZDWHUKHDWHU
:HDSSUHFLDWH\RXUFRQ¿GHQFHLQRXUSURGXFWV
Read and understand this instruction
manual and the safety messages
herein before installing, operating or
servicing this water heater.
Failure to follow these instructions and
safety messages could result in death
or serious injury.
This manual must remain with the
water heater.
MODELS
BTH 300(A)/400(A)/500(A)
SERIES 300 & 301
INSTALLATION - OPERATION - SERVICE
- MAINTENANCE - LIMITED WARRANTY
WARNING: If the information in these
instructions is not followed exactly, a fire
or explosion may result causing property
damage, personal injury or death.
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 electrical 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.




ANSI/NSF-5
LOW LEAD
CONTENT
7HQQHVVHH:DOW]3DUNZD\
$VKODQG&LW\71
www.hotwater.com

Summary

Safe Installation, Use and Service

General Safety Information

Precautions

General precautions to follow before operating or servicing the water heater.

Grounding Instructions

Instructions for proper electrical grounding of the water heater.

Hydrogen Gas Flammable

Warning about potential hydrogen gas buildup and explosion hazard.

Fire and Explosion Hazards

Risks from flammable vapors, gas pressure, and clearances.

Breathing Hazard - Carbon Monoxide Gas

Risks of CO exposure and need for ventilation.

Electrical and Property Damage Hazards

Covers electrical shock and property damage from leaks.

Introduction

Qualifications

Preparing for the Installation

Features and Components

Basic Operation

Top View

Components (All Models)

Side Views

Installation Considerations

Rough in Dimensions

Gas Line Requirements

Covers connection size, pressure, and minimum line size.

Locating the Water Heater

Clearance to Combustible Materials

Intake Air and Vent Pipe Clearances

Installation Requirements

Gas Supply Systems

Requirements for low/high pressure gas, regulators, and general supply.

Power Supply Requirements

Covers power, dedicated wiring, breakers, and noise issues.

Mixing Valves

Thermal Expansion

Temperature-Pressure Relief Valve

T&P Valve Discharge Pipe Requirements

Specifies requirements for the T&P valve discharge pipe.

Condensate Drain

Combustible Material Storage

Contaminated Air

Air Requirements

Confined Space Air Requirements

Covers air needs in confined spaces and tight construction.

Fresh Air Openings for Confined Spaces

Installation Requirements - Commonwealth of Massachusetts

Massachusetts Specific Requirements

General MA requirements, inspection, and exemptions.

Carbon Monoxide Detector & Signage Requirements

CO detector and vent signage mandates.

Manufacturer Venting System Requirements

Venting Installation

General Venting Instructions

Essential instructions applicable to all venting installations.

Approved Materials

Venting Requirements

Pipe Requirements

Covers size, length, clearances, and elbows for vent pipes.

Venting Limitations

Venting Installation Sequence

Power Vent Installation

Direct Vent Installation

Direct Vent Air Intake Moisture Protection

Vertical Termination Installation

Sidewall Termination Installation

Polypropylene Installations

AL29-4 C Vent Installations

Concentric Termination Installation

6 Inch Concentric Termination Installation

Multiple Concentric Termination Clearances

Clearance Types

Low Profile Vent Installation

Termination Clearances Sidewall Power Vent

Termination Clearances Sidewall Direct Vent

Water Heater Installation

Condensate Drain Installation

Supply Gas Line Installation

Gas Line Sizing

Gas Line Connection

Gas Line Leak Testing

Procedures for testing gas lines for leaks and purging.

Electrical & Power Connections

Control System Interfaces

Water Piping Requirements

T&P Valve Discharge Pipe

Temperature Regulation

High Temperature Limit Control (ECO)

Thermostat Control

Information on thermostat settings and scald hazard.

Control System Operation

User Settings & Control System Menus

Temperatures Menu

Temperatures Menu (Cont)

Current Fault

Start Up

Start Up Preparation

Covers prior steps, filling, initial startup, equipment, and general prep.

Lighting & Operation Label

For Your Safety Read Before Lighting

Critical safety warnings before lighting the appliance.

Operating Instructions

Step-by-step guide for operating the water heater.

Supply Gas Pressure Adjustment

To Turn Off Gas Supply

Troubleshooting

Installation Checklist

A list of critical installation requirements to check.

Sequence of Operation

Sequence of Operation Flow Chart

Operational Problems

Common Operational Issues

Covers installation errors, rough operation, momentary ignition, and no hot water.

Control System States & Diagnostics

Control System States & Diagnostics

Alerts, lockouts, and diagnostic checks.

Fault and Alert Messages

Maintenance

Maintenance Schedule

Precautions

Safety precautions to follow during maintenance.

Draining and Flushing

Sediment Removal

Lime Scale Removal

Temperature-Pressure Relief Valve Test

Vent System

Wiring Diagram

Water Piping Diagrams

Commercial Water Heater Limited Warranty

Warranty Coverage and Terms

A.O. Smith BTH 400 Specifications

General

Category	Water Heater
Manufacturer	A.O. Smith
Model	BTH 400
Fuel Type	Natural Gas
Gas Connection	3/4" NPT
Voltage	120V
Thermostat	Electronic
Pressure Rating	150 PSI
Insulation	2" Non-CFC Foam