OPERATION OF THESE FANS CAN PRODUCE A NEGATIVE DRAFT IN THE AREA OF THE WATER HEATER PREVENTING THE PRODUCTS OF COMBUSTION FROM EXHAUSTING THROUGH THE CHIMNEY OR VENT PIPE.
The venting of the water heater should be inspected by a qualified service technician at the time of installation and periodically thereafter to ensure a
DO NOT OBSTRUCT THE FLOW OF COMBUSTION AND VENTILATING AIR. ADEQUATE AIR FOR COMBUSTION AND VENTILATION MUST BE PROVIDED FOR SAFE OPERATION.
EXTENDED NON-USE PERIODS
WARNING
HYDROGEN GAS CAN BE PRODUCED INAHOT WATER SYSTEM SERVED BY THIS HEATER THAT HAS NOT BEEN USED FOR A LONG PERIOD OF TIME (GENERALLY TWO WEEKS OR MORE). HYDROGEN GAS IS EXTREMELY FLAMMABLE. To reduce the risk of injury under these conditions, it is recommended that the hot water faucet be opened for several minutes at the kitchen sink before using any electrical appliance connected to the hot water system. If hydrogen is present, there will probably be an unusual sound such as air escaping through the pipe as the water begins to flow. THERE SHOULD BE NO SMOKING OR
OPEN FLAME NEAR THE FAUCETAT THE TIME IT IS OPEN.
INSULATION BLANKETS
Insulation blankets available to the general public for external use on gas water heaters are not approved for use on your A.O. Smith water heater. The purpose of an insulation blanket is to reduce the standby heat loss encountered with storage tank water heaters. Your A.O. Smith water heater meets or exceeds the ASHRAE/IES
WARNING
Should you choose to apply an insulation blanket to this heater, you should follow these instructions. Failure to follow these instructions can result in fire, asphyxiation, serious personal injury or death.
•Do not apply insulation to the top of the water heater, as this will interfere with safe operation of drafthood.
•Do not cover the temperature & pressure relief valve.
•Do not cover the instruction manual. Keep it on the side of the water heater or nearby for future reference.
•Do obtain new labels from A.O. Smith for placement on the blanket directly over the existing labels.
HIGH ALTITUDE INSTALLATIONS
WARNING
INSTALLATIONS ABOVE 2000 FEET (610 METERS) REQUIRE REPLACEMENT OF THE BURNER ORIFICE IN ACCORDANCE WITH SECTION 8.1.2 OF THE NATIONAL FUEL GAS CODE (ANSI Z223.1). FAILURE TO REPLACE THE ORIFICE WILL RESULT IN IMPROPERAND INEFFICIENT OPERATION OF THE APPLIANCE RESULTING IN THE PRODUCTION OF INCREASED LEVELS OF CARBON MONOXIDE GAS IN EXCESS OF SAFE LIMITS WHICH COULD RESULT IN SERIOUS PERSONAL INJURY OR DEATH.
You should contact your gas supplier for any specific changes which may be required in your area.
As elevation above sea level is increased, there is less oxygen per cubic foot of air. Therefore, the heater input rate should be reduced at high altitudes for satisfactory operation with the reduced oxygen supply. Failure to make this reduction would result in an overfiring of the heater causing sooting, poor combustion and/or unsatisfactory heater performance.
REQUIREMENTS
Ratings specified by manufacturers for most appliances apply for elevations up to 2000 feet. For elevations above 2000 feet, ratings must be reduced at the rate of 4% for each 1000 feet above sea level. For example, if a heater is rated at 120,000 Btuh at sea level, to rate the heater at 4000 feet, you subtract 4 (once for each thousand feet) x.04 (4% input reduction) x 120,000 Btuh (original rating) from the original rating. Therefore, to calculate the input rating at 4,000 feet: 4 x .04 x 120,000 =19,200 Btuh, 120,000 - 19,200 = 100,800 Btuh. At 6000 feet the correct input rating should be 91,200 Btuh.
The input reduction is primarily achieved by reducing the size of the main burner orifices. To do this, the main burner orifices require replacement with orifices sized for the particular installation elevation. Correct orifice sizing and parts may be obtained from A.O. Smith Water Products Company. When ordering, be sure to state the model number and the altitude of the location where the water heater is being installed.
Upon completion of derating of the heater, adjustment to the gas pressure regulator may be required. See CHECKING THE INPUT section in this manual for inlet and manifold pressure requirements.
Also due to the input rating reduction required at high altitudes, the output rating of the appliance is also reduced and should be compensated for in the sizing of the equipment for application.
FEATURES
THE ELIMINATOR™ (SELF-CLEANING SYSTEM)
These units include The Eliminator
Note: The inlet tube may have 1, 3 or 7 cross tubes.
FIGURE2
For proper function, the Eliminator must be oriented correctly. There is a marked range on the pipe nipple that must be aligned with the top of the inlet spud (check for label on the appliance) to assure proper operation. Please check to confirm that the marked range is in alignment with the top of the spud. A pipe union is supplied with the Eliminator to help eliminate the
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