ATH HEATNET KN Series, Operation Instructions Manual, Page: 110 / 144

DEFAULT SETTINGS & MENU ITEM DESCRIPTIONS HeatNet Control V3 3.x
Page 110
ALARM TYPE FAULT FAULT/WARNING
FAULT will stop the boiler when the Delta T has exceeded its
setting.
WARNING will allow the boiler to continue running but produce
the Warning message.
EXCHANGER
DELTA T
AUTO
60
°
F
AUTO
1 to 120
°
F
Settings are Automatic if running DELTA T in the HIGH and LOW
protection setting.
This is the maximum differential temperature the heat exchanger can
see before the LIMIT RATE feature is activated, and a log entry is
made.
LIM TO HALF RATE
YES
N/A
YES
Not Available if running DELTA T in the HIGH and LOW
protection setting.
Limit to Half Rate: When set to YES, and the maximum differential
temperature (delta T) has been exceeded, the fire rate called for is cut
in half. In other words: if we are calling for 80% modulation and
have exceeded the delta T, the boiler will only fire at 40%. The delta
T needs to drop 10
°
F below the maximum delta T to reset this limit.
The message “½ INPUT” will be displayed on a MEMBER boiler
and a MASTER Boiler will display the Modulation % for the system
even though it is running at ½ of this rate. This method helps protect
the heat exchanger from damage due to excessive delta T’s. If this
MASTER boiler is running.
SEND RETURN RETURN
RETURN, SYSTEM
RETURN
This setting is used by the MASTER boiler to select which Return
sensor temperature to send to all MEMBER boilers. The Return
temperature will then be used by the MEMBER boilers (usually non-
condensing) to determine if they can be called by the MASTER to
run.
If a System Return sensor is available on the MASTER, set this
setting to SYS RET. If only a Return sensor is available, set to
RETURN.
TEMPERATURE
DISABLE
OFF
SYSTEM RETURN,
RETURN, OFF
This setting is used by a MEMBER boiler (primarily a non-
condensing type) to determine which return sensor to look at when
determining if it is safe to fire. Its purpose is to keep non-condensing
boilers from firing in a condensing mode.
SYS RET the boiler will use the Return temperature sent from the
MASTER boiler.
RETURN the boiler will use its own Return sensor. If it is set to
OFF, then this feature will not be used.
If a sensor is selected, then the Boiler will determine if the Return
sensor’s temperature is below the TEMP< XXX setting in the
following menu. If the Return temperature is lower, the boiler will
take itself offline from the MASTER. Informing the MASTER that it
can’t run. The message “
blr offline”
will be displayed in the Status
screen.