American Water Heater ABCG3 - Manual (Page 6)

6
HIGH ALTITUDE INSTALLATIONS
WARNING
INSTALLATIONS ABOVE 2000 FEET (610 METERS) REQUIRE
REPLACEMENT OF THE BURNER ORIFICE IN ACCORDANCE
WITH THE NATIONAL FUEL GAS CODE (ANSI Z223.1). FAILURE
TO REPLACE THE ORIFICE WILL RESULT IN IMPROPER AND
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
American Water Heater 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 (Self-Cleaning System) installed
in the front water inlet, see Figure 2. The Eliminator must be oriented
correctly for proper function. There is a marked range on the pipe
nipple portion of the Eliminator, that must be aligned with the top of
the inlet spud. A label above the jacket hole has an arrow that will
point to the marked portion of the pipe nipple if the orientation is
correct. If the arrow does not point within the marked range on the
pipe nipple, adjust the pipe nipple to correct. A pipe union is supplied
with the Eliminator to reduce the probability of misaligning the
Eliminator accidentally while tightening the connection to the inlet
water supply line. Improper orientation of the Eliminator can cause
poor performance of the heater and can significantly reduce outlet
water temperatures during heavy draws.
Note: The inlet tube may have 1, 3 or 7 cross tubes. - FIGURE 1
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
possibility of changing the orientation by accidentally
overtightening the inlet supply. Improper orientation of the
Eliminator may cause temperature buildup issues or spells of
colder than usual water temperatures.
HIGH LIMIT SWITCH
The digital thermostat (Fig. 2) contains the high limit (energy
cutoff) sensor. The high limit switch interrupts main burner gas
flow should the water temperature reach 203°F (95°C).
In the event of high limit switch operation, the appliance cannot
be restarted unless the water temperature is reduced to
approximately 120°F (49°C). The high limit reset button on the
front of the control then needs to be depressed.
Continued manual resetting of high limit control, preceded by
higher than usual water temperature is evidence of high limit
switch operation. The following is a possible reason for high
limit switch operation:
• A malfunction in the thermostatic controls would allow the
gas valve to remain open causing water temperature to exceed
the thermostat setting. The water temperature would continue
to rise until high limit switch operation.
Contact your dealer or service agent if continued high limit switch
operation occurs.
DIGITAL THERMOSTAT
FIGURE 2
ELECTRONIC IGNITION CONTROL
Each heater is equipped with a ignition module. The solid sate
ignition control (Fig. 3), ignites the main burner by utilizing a
silicone nitride ignitor. The silicone nitride ignitor shuts off during
the heating cycle and the main burner flame is sensed through
a remote flame sensor integral to the silicone nitride ignitor
assembly. The ignition control will try to ignite the main burner
three times before lockout. Then it waits one hour before trying
again to ignite the main burners. This is a continuous cycle.