A.O. Smith BTH 120-250(A) warranty Table of Contents, Features

TABLE OF CONTENTS

	PAGE		PAGE
ROUGH-IN DIMENSIONS	2	Water Line Connections	14
FOREWORD	2	Heater Wiring	14
FEATURES	3,4	OPERATION	15
Water Temperature Control	3	Sequence of Operation	15
High Limit Switch (E.C.O.)	4	Self Diagnostic Controller	15
Dishwashing Machine Requirement	4	Gas Value LEDs Flashing	15
Circulating Pump	4	Error Codes	16
INSTALLATION INSTRUCTIONS	4-13	Fault Conditions	16
Required Ability	4	No Incoming Line Voltage	16
Insulation Blankets	4,5	No Low Voltage	16
Locating The Heater	5	Temperature Probe Fault	16
Clearances	5	E.C.O. Switch Open	17
Hard Water	6	Control Bad	17
Air Requirements	6	Combustion Air Blockage	17
Mechanical Exhausting of Room Air	6	PRIOR TO START-UP	18
Unconfined Space	6	Required Ability	18
Confined Space	6	OPERATIINGINSTRUCTIONS	18
Chemical Vapor Corrosion	6	Adjustment Procedure (Initial Start-Up)	18
Venting	6	Lighting Instructions	19
Vent Pipe Termination	6-8	Cathodic Protection	20
Direct Venting	8	Precautions	20
Direct Vent Terminal Installation (Sidewall)	8	GENERAL INFORMATION	20
Installation Sequence	9	Power Burner	20
Vertical Vent Terminal Installation	10	High Limit	20
Installation Sequence	10	High Altitude Installations	20
Installation of Vent System	10 ,11	MAINTENANCE	20
Vent Pipe Preparation	11	General	20
CONTROL AND SWITCHES	11,12	Maintenance Schedule	20
Blower Prover Switch	11	Flushing	21
Blocked Outlet Prover Switch	12	Draining	21
Blocked Inlet Prover Switch	12	Sediment Removal	21
Low Gas Pressure Switch	12	Lime Scale Removal	21
On/Off Switch	12	Anode Inspection and Replacement	21,22
Hot Surface Igniter	12	Drain Valve and Access Panels	22
GAS PIPING	12	Relief Valve	22
Connection of Gas Pipe	13	Circulating Pump	22
Purging	13	Vent System	22
Gas Meter Size - City Gases Only	13	INSTALLATION DIAGRAMS	23 - 27
Gas Pressure Regulation	13	Manifold Kits	28
Gas Valves	13	CHECKLISTAND SERVICE INFORMATION	29
SYSTEM CONNECTIONS	13	TROUBLE-SHOOTING	29,30
Thermometers	13	REPLACEMENTPARTS	30
Relief Valve	13	LIMITED WARRANTY	31

FEATURES

IMPORTANT

IT IS REQUIRED THATA QUALIFIED SERVICE TECHNICIAN PERFORM THE INITIAL FIRING OF THE HEATER. AT THIS TIME THE USER SHOULD NOT HESITATE TO ASK THE TECHNICIAN ANY QUESTIONS WHICH HE MAY HAVE IN REGARD TO THE OPERATIONAND MAINTENANCE OF THE UNIT.

A CHECKLISTAND SERVICE INFORMATION section are included at the rear of this manual. By using this checklist the user may be able to make minor operational adjustments and save himself unnecessary service calls. However, the user should not attempt repairs which are not listed in this section.

WATER TEMPERATURE CONTROL

DANGER

THIS WATER HEATER IS EQUIPPED WITHANADJUSTABLE THERMOSTAT TO CONTROL WATER TEMPERATURE. HOT WATER TEMPERATURES REQUIRED FOR AUTOMATIC DISHWASHER AND LAUNDRY USE CAN CAUSE SCALD BURNS RESULTING IN SERIOUS PERSONAL INJURYAND/ OR DEATH. THE TEMPERATURE AT WHICH INJURY OCCURS VARIES WITH THE PERSON’S AGE AND THE TIME OF THE EXPOSURE. THE SLOWER RESPONSE TIME OF CHILDREN, AGED OR DISABLED PERSONS INCREASES THE HAZARDS TO THEM. NEVER ALLOW SMALL CHILDREN TO USE A HOT WATER TAP, OR TO DRAW THEIR OWN BATH WATER. NEVER LEAVE A CHILD OR DISABLED PERSON UNATTENDED IN A BATHTUB OR SHOWER.

THE WATER HEATER SHOULD BE LOCATED IN AN AREA WHERE THE GENERAL PUBLIC DOES NOT HAVE ACCESS TO SET TEMPERATURES.

The water temperature is controlled using the Temperature Control Button on the Display at the front of the unit (See Figure 1). This control utilizes two temperature probes to determine the tank temperature. The primary temperature probe is located at the top of the tank and the other is near the water inlet.

The temperature may be adjusted from 80°F/27°C to 185°F/85°C. The thermostat was adjusted to 120°F/49°C before the heater was shipped from the factory. It is recommended that lower water temperatures be used to avoid the risk of scalding. It is further recommended, in all cases,

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