A.O. Smith 650, GB/GW-300, 500, 750 SERIES warranty Lighting Instructions, Risk of Scalds

LIGHTING INSTRUCTIONS

These models have an automatic hot surface ignition system mounted on the combustion chamber panel inside the front jacket. This hot surface igniter ignites the main burner gas whenever the system control calls for heat.

Before proceeding with operation of the unit, make sure the boiler and system are filled with water and all air is expelled from the boiler, radiator tank(s) and piping.

WARNING

THE MAIN MANUAL GAS SHUT-OFF VALVE MUST HAVE BEEN CLOSED FOR AT LEAST FIVE (5) MINUTES BEFORE LIGHTING. This waiting period is an important safety step. Its purpose is to permit gas that might have accumulated in the combustion chamber to clear. IF YOU DETECT GAS AT THE END OF THE PERIOD DO NOT PROCEED WITH LIGHTING. RECOGNIZE THAT GASODOR,EVENIFITSEEMSWEAK,MAYINDICATEPRESENCE OFACCUMULATEDGASSOMEPLACEINTHEAREAWITHARISK OF FIRE OR EXPLOSION.

WARNING

THERE IS A RISK IN USING FUEL BURNING APPLIANCES SUCH AS GAS WATER BOILERS IN ROOMS, GARAGES OR OTHER AREAS WHERE GASOLINE AND OTHER FLAMMABLE LIQUIDS ARE USED OR STORED, OR ENGINE-DRIVEN EQUIPMENT OR VEHICLES ARE STORED, OPERATED OR REPAIRED. FLAMMABLE VAPORS ARE HEAVYAND TRAVEL ALONG THE FLOOR AND MAY BE IGNITED BY THE BOILER'S MAIN BURNER FLAMES CAUSING FIRE OR EXPLOSION. Some local codes permit operation of gas appliances if installed 18 inches or more above the floor. This may reduce the risk if location in such an area cannot be avoided.

TEMPERATURE REGULATION

DANGER

HOT WATER TEMPERATURES REQUIRED FOR AUTOMATIC DISHWASHER AND LAUNDRY USE CAN CAUSE SCALD BURNS RESULTING IN SERIOUS PERSONAL INJURY AND/ OR DEATH. THE TEMPERATURE AT WHICH INJURY OCCURS VARIES WITH THE PERSON'S AGE AND TIME OF 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.

It is recommended that lower water temperatures be used to avoid the risk of scalding. It is further recommended, in all cases, that the water temperature be set for the lowest temperature which satisfies the user's hot water needs. This will also provide the most energy efficient operation of the water heater and minimize scale formation.

SETTING THE WATER HEATER TEMPERATURE AT 120°F WILL REDUCE THE RISK OF SCALDS. Some states require settings at specific lower temperatures. Table 1 below shows the approximate time-to-burn relationship for normal adult skin.

Table 1: Risk of Scalds

Temperature	Time to Produce 2nd & 3rd
Setting	Degree Burns on Adult Skin
Over 170°F	Nearly instantaneous
160°F	About 1/2 second
150°F	About 1-1/2 seconds
140°F	Less than 5 seconds
130°F	About 30 seconds
120°F or less	More than 5 minutes

BOILER LOCATION

Water heater life depends upon water quality, water pressure and the environment in which the water heater is installed. Water heaters are sometimes installed in locations where leakage may result in property damage, even with the use of a drain pan piped to a drain. However, unanticipated damage can be reduced or prevented by a leak detector or water shutoff device used in conjunction with a piped drain pan. These devices are available from some plumbing supply wholesalers and retailers, and detect and react to leakage in various ways:

•Sensors mounted in the drain pan that trigger an alarm or turn off the incoming water to the water heater when leakage is detected.

•Sensors mounted in the drain pan that turn off the water supply to the entire home when water is detected in the drain pan.

•Water supply shutoff devices that activate based on the water pressure differential between the cold water and hot water pipes connected to the water heater.

•Devices that will turn off the gas supply to a gas water heater while at the same time shutting off its water supply.

BLOCKED VENT SHUT-OFF SYSTEM

The Boiler is equipped with a blocked vent shut-off system which will close the gas valve and shut off the main burner gas when there is excessive pressure in the vent system due to a partially or completely blocked vent system.

DO NOT ATTEMPT TO OPERATE THE BOILER if this situation occurs. Shut the boiler off before performing all the steps shown in "TO TURN OFF GAS TO APPLIANCE" section of the Lighting and Operating Instructions.

Contact a qualified service agent to inspect the unit and vent system and correct the problem.

VENT SYSTEM

The flue products are corrosive in nature and if the boiler is vented horizontally the flue gases are at a higher pressure than

3