losses and may satisfy your normal hot water needs. If hot water use is expected to be more than normal, a higher thermostat setting may be required to meet the increased demand. When leaving your home for extended periods (vacations, etc.) Set the electronic control display tem- perature “COOLER” 
button to its lowest setting. This will maintain the water at low temperatures with minimum energy losses and prevent the tank from freezing during cold weather.
Gas Control Valve/Thermostat Settings
HOTTER 
COOLER
Electronic Control Display
FIGURE 21.
Operational Conditions
Condensation
Whenever the water heater is filled with cold water, some condensate will form while the burner is on. A water heater may appear to be leaking when in fact the water is condensation. This usually happens when:
a.A new water heater is filled with cold water for the first time.
b.Burning gas produces water vapor in water heaters, par- ticularly high efficiency models where flue temperatures are lower.
c.Large amounts of hot water are used in a short time and the refill water in the tank is very cold.
Moisture from the products of combustion condense on the cooler tank surfaces and form drops of water which may fall onto the burner or other hot surfaces to produce a “sizzling” or “frying” noise.
Excessive condensation can cause burner flame problems due to water running down the flue tube onto the main burner.
Because of the suddenness and amount of water, condensation water may be diagnosed as a “tank leak”. After the water in the tank warms up (about
Do not assume the water heater is leaking until there has been enough time for the water in the tank to warm up.
An undersized water heater will cause more condensation. The water heater must be sized properly to meet the family’s demands for hot water including dishwashers, washing machines and shower heads.
Excessive condensation may be noticed during the winter and early spring months when incoming water temperatures are at their lowest.
Good venting is essential for a gas fired water heater to operate properly as well as to carry away products of combustion and water vapor.
It is always recommended that a suitable metal drain pan be installed under the water heater to protect the area from water damage resulting from normal condensation production, a leaking tank or piping connections. Refer to the “Location Requirements” section.
Water Heater Sounds
During the normal operation of the water heater, sounds or noises may be heard. These noises are common and may result from the following:
1.Normal expansion and contraction of metal parts during periods of
2.Condensation causes sizzling and popping within the burner area and should be considered normal.
3.Sediment buildup in the tank bottom will create varying amounts of noise and may cause premature tank failure. Drain and flush the tank as directed under the “Draining and Flushing” section.
Smoke/Odor
The water heater may give off a small amount of smoke and odor during the initial
Safety Shut-off
This water heater is designed to automatically
1.The burner flame is extinguished for any reason.
2.The water temperature exceeds 195°F (91°C).
3.Excessive build up of dust on the louvers of the air intake chamber. See Maintenance of your Water Heater Section.
This unit is also equipped with a flammable vapor sensor (FV Sensor), designed to shut off the gas supply in the event the water heater has been exposed to flammable vapors (e.g., spilled gasoline).
A high temperature limit switch or ECO (Energy Cut Off) in the tank is used to shut off the unit if the water temperature exceeds 195°F (91°C). The ECO is a
23
