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KN INSTALLATION AND OPERATION INSTRUCTIONS
Figure 24b Boiler sequence of operation, fault states and HeatNet control display information
Figure 24a HeatNet control display during operation
Starting the boiler
(continued)
Normal condition
Blower status
Time
Ignition
status
Gas valve
status
Display
(upper left)
Standby (not heat call)
OFF
OFF
OFF
STANDBY
Start (call for heat)
OFF (Flow switch and other interlocks in
the flow switch circuit must prove)
10 seconds
OFF
OFF
FLOW WAIT
OFF
if supply temperature is above the
bottom of the heat band; circulator runs,
but boiler does not fire yet
Demand
OFF
OFF
HEATING
ON at purge RPM (55% of maximum)
when supply temperature drops below
the bottom of the heat band
10 seconds
PRE PURGE
Ignition trial
ON at ignition RPM (30% of maximum)
4 seconds
ON
ON
IGN 30%
Flame is sensed
(Stabilization period)
ON at ignition RPM (30% of maximum)
6 seconds
OFF
ON
IGN 30%
Operate on demand
ON at RPM based on demand (control
determines firing rate % based on
demand and rate of change, etc.)
Demand
OFF
ON
RUN %XXX
End call for heat
ON at purge RPM (55% of maximum)
OFF
OFF
POST PRGE
Ignition failure
ON at purge RPM
Boiler restarts a normal sequence
Control will try 3 times, then lockout
Normal display unless three attempts fail, then shows:
IGN LOCKOUT
(alternating to:)
Date & Time of lockout
Flame failure
ON at purge RPM for postpurge
Boiler restarts a normal sequence
Normal display unless ignition is unsuccessful three times after
restart
To reset the HeatNet control from lockout:
Turn the boiler on/off switch OFF, then back ON.
For more information:
See the
KN
Control manual for additional information and troubleshooting.
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