A.O. Smith BTH 120 Series - User Manual

MODELS COVERED: BTH 120 THRU 500
SERIES 100, 101 AND
BTH 400/500 SERIES 104
500 Tennessee Waltz Parkway
Ashland City, TN 37015
PRINTED IN THE U.S.A. 1012 316586-002
SERVICING SHOULD ONLY BE PERFORMED BY A QUALIFIED SERVICE TECHNICIAN
Service Handbook
COMMERCIAL GAS HIGH EFFICIENCY WATER HEATERS
http://waterheatertimer.org/How-to-troubleshoot-gas-water-heater.html

Summary

INTRODUCTION

QUALIFICATIONS

TOOLS REQUIRED

GENERAL INFORMATION

GAS PRESSURE SPECIFICATIONS

GAS SUPPLY SYSTEMS

SUPPLY GAS REGULATOR

Provides instructions and requirements for installing a positive lock-up gas pressure regulator.

GAS PRESSURE QUICK TIPS - BTH 120;150

HIGH ALTITUDE INSTALLATIONS - BTH 120-150

Provides guidance for BTH 120-150 installations at high altitudes.

GAS PRESSURE QUICK TIPS - BTH 199;250

GAS ORIFICE

Describes the gas orifices used in BTH 199 and 250 models.

GAS PRESSURE QUICK TIPS - BTH 300;400;500

VENTING CATEGORY AND MATERIALS

TYPES OF VENTING

Covers Cyclone, Direct, Conventional, and Concentric Venting methods.

VENT MATERIALS

Lists approved materials for vent systems.

VENTING TABLES - BTH 120-250

VENTING TABLES - BTH 300;400;500

CONCENTRIC VENTING

VENT CONDENSATION

POWER VENT SIDEWALL CLEARANCES

DIRECT VENT SIDEWALL CLEARANCES

DIRECT VENT TERMINATION SPECIFICATIONS

DIRECT VENTING INSTALLATION SETUP

CONTROL OVERVIEW

ADJUSTING TANK TEMPERATURE AND SETTINGS

CHANGING DISPLAY UNITS

FAULT AND WARNING CONDITIONS OVERVIEW

ACCESSING FAULT;WARNING DETAILS

FAULT CODE REFERENCE

VIEWING FAULT HISTORY AND HEATER INFORMATION

TYPICAL CONTROL SEQUENCE

CONTROL SEQUENCE FLOW CHART

CENTRAL CONTROL BOARD (CCB) OVERVIEW

GAS CONTROL VALVE - BTH 120

GAS CONTROL VALVE - BTH 150

GAS CONTROL VALVE - BTH 199;250

GAS CONTROL VALVE;ORIFICE CHART - BTH 300;400

GAS CONTROL VALVE;ORIFICE CHART - BTH 400;500

PRESSURE SWITCHES - ALL MODELS

PRESSURE SWITCHES - BTH 120-250

PRESSURE SWITCHES - BTH 300;400;500

COMPONENT CONNECTIONS: IGNITER, SENSOR, ANODES

IGNITER, FLAME SENSOR & CONTROL TIMING

BLOWER SPEED CONTROL - BTH 199;250

VARIABLE FREQUENCY DRIVE (VFD) - BTH 400;500

VFD BLOWER SPEED;PRESSURE READINGS

WIRING DIAGRAM - BTH 120-300

WIRING DIAGRAM - BTH 400;500

A.O. Smith BTH 120 Series Specifications