Install Instructions
TR/HL and SMART Series
Thermostat Replacement Instructions
9
Adjusting the Water Heater Thermostat
Water heater thermostat is factory set to its low-
est temperature.  This may or may not be suit-
able for your needs.
Turn thermostat knob clockwise to
increase water temperature.
Turn thermostat knob counter-clockwise 
to decrease water temperature.
Studies have indicated that dangerous bacte-
ria,  including  legionella,  pneumophila,  can
form  in  the  potable  water  distribution  sys-
tem if certain minimum water temperatures
are  not  maintained.  Contact  your  local
health department for more information.
• Check water temperature at a hot water faucet
immediately  after  first  heating  cycle.    Further
temperature  adjustment  may  be  necessary  as
water  heating  system  is  used.    Recheck  water
temperature at faucet after adjustment.
• When adjusting thermostat, be sure boiler limit
control is set at a minimum of 20ºF higher than
the desired domestic water temperature.
WARNING
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Temperature
Down
Temperature
Up
Temperature
Up
Temperature
Down
TR Series Knob
HL Series Knob
SMART Series Knob
2008-3 P3 TR/HL & Smart Therm. Repl. 
Date: 6/9/09 









