Crown Boiler TWZ Series, Installation Instructions Manual

Page: 37 / 52

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FIGURE 12.3 LED Legend and TEST/SETTINGS Button
5) ECONOMY - ACTIVE - Indicates that the thermal targeting function is active and the control will reduce boiler temperature
to conserve fuel. The Economy feature is activated using the ECONOMY dial. (See “Setting the Economy Feature” on page
29 for more information).
6) ECONOMY - TARGET - When the Economy feature is active, the control continually sets target temperatures below the
high limit setting to maximize fuel efficiency. When the boiler water reaches the target temperature, the LED illuminates
and the burner will shut down. The boiler water will continue to circulate and heat the house as long as the thermostat call
continues. The LED will stay lit until the boiler temperature drops below the differential set point at which point the boiler
will be allowed to fire again. See Differential explanation on page 31. NOTE: This LED illuminates regularly during normal
boiler operation.
7)
TEST/SETTINGS
BUTTON -
To Test Low Water Cut-Off:
Press and hold the Test/ Settings button for 5 seconds. The
display will read
LCO
. The red Low Water light should illuminate and the burner circuit (
B1
and
B2
) should de-energize.
NOTE:
The control must be installed with a Hydrolevel Electro-Well™ for low water cut-off functionality (see page 28 for
more details).
To View Current Settings:
Press and release the Test/Settings Button in short intervals to sequentially display
the following settings:
HIGH LIMIT SETTING
HL
LOW LIMIT SETTING
LL
ECONOMY SETTING
ECO
CURRENT TARGET TEMPERATURE
ooo
The display will return to boiler temperature (default) if Test/Settings Button in not pressed for 5 seconds.