A.O. Smith FMD 40 Water Heater User Manual


 
21
VERY HOT= approx. 160°F (71°C)
About 1/2 second
C = approx. 150°F (66
°C) About 1-1/2 seconds
B = approx. 140°F (60°C) Less than 5 seconds
A = approx. 130°F (54°C) About 30 seconds
= approx. 120°F (49°C) More than 5 minutes
= approx. 80°F (27°C)
- - - - - - - - - - - - - - - -
FIGURE 36.
FOR YOUR INFORMATION
START UP CONDITIONS
CONDENSATE
Whenever the water heater is lled 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 lled with cold water for the rst time.
b. Burning gas produces water vapor in water heaters, particularly
high ef ciency models where ue temperatures are lower.
c. Large amounts of hot water are used in a short time and the re ll
water in the tank is very cold.
Moisture from the products of combustion condense on the cooler
NOTE: A water temperature range of 120°F-140°F (49°C-60°C) is
recommended by most dishwasher manufacturers.
The thermostat of this water heater has been factory set at its lowest
position. It is adjustable and must be reset to the desired temperature
setting to reduce the risk of scald injury. The mark ( ) indicative
of approximately 120°F (49°C) is preferred starting point. Some
Provinces may have a requirement for a lower setting.
Turn the water temperature dial clockwise (
) to decrease
the temperature, or counterclockwise (
) to increase the
temperature.
Should overheating occur or the gas supply fail to shut off, turn off
the manual gas control valve to the appliance.
FIGURE 35.
Temperature Time to Produce 2nd & 3rd
Settings Degree Burns on Adult Skin
Short repeated heating cycles caused by small hot water uses can
cause temperatures at the point of use to exceed the thermostat
setting by up to 30°F (16.7°C). If you experience this type of use
you should consider using lower temperature settings to reduce
scald hazards.
HOTTER WATER CAN SCALD: Water heaters are intended to
produce hot water. Water heated to a temperature which will satisfy
space heating, clothes washing, dish washing, and other sanitizing
needs can scald and permanently injure you upon contact. Some
people are more likely to be permanently injured by hot water than
others. These include the elderly, children, the in rm, or physically/
mentally handicapped. If anyone using hot water in your home
ts into one of these groups or if there is a local code or state law
requiring a certain temperature water at the hot water tap, then
you must take special precautions. In addition to using the lowest
possible temperature setting that satis es your hot water needs,
a means such as a mixing valve should be used at the hot water
taps used by these people or at the water heater. Mixing valves
are available at plumbing supply or hardware stores, see Figure
2. Follow manufacturer’s instructions for installation of the valves.
Before changing the factory setting on the thermostat, read the
“Temperature Regulation” section in this manual, see Figures 35
and 36.
Never allow small children to use a hot water tap, or to draw their own
bath water. Never leave a child or handicapped person unattended
in a bathtub or shower.
TEMPERATURE REGULATION
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 pilot outage due to water running
down the ue tube onto the main burner and putting out the pilot.
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 1-2 hours), the condition should disappear.
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.
Lowest
Setting