HydroTherm HeatNet KN -6 User Information page 103

APPENDIX A
WTR FLW LOCAL:
Once the HeatNet series boiler receives a call for heat, it
closes the LOCAL PUMP/VALVE relay. It then waits 10
seconds or more (adjustable) to prove flow. If there is no
flow, the flow switch alarm will be set. Every 10 seconds
the circulator pump relay will cycle ON for 10 seconds
and then OFF for 10 seconds to try and establish flow.
The interlock connection is located on J5B, WTR FLW.
IGNITION CTRL ALARM:
The ignition control alarm is displayed if the ignition
control detects a fault. This could be a flame failure, air
proving switch, or other fault associated with the ignition
control. When this fault occurs, you will need to refer to
the ignition control for the reason.
COMBUST AIR DAMPER:
If the combustion air damper has been selected for use
(AUX FUNCTIONS), and the proof switch does not
make, this fault will be displayed.
When the master boiler receives a call for heat and needs
to start a boiler, the DAMPER relay closes on J13. If the
combustion air damper does not prove within the proof
time specified in the combustion air damper menu, the
boiler will not start and then display the fault. A
combustion damper fault on a boiler can only be cleared
by power cycling.
OPEN ******* SENSOR :
If the open sensor fault is displayed, the sensor in the position
reported was originally detected, but has since opened. The
boiler will shut down on any OPEN sensor except the
OUSTSIDE AIR sensor.
SHORTED ******* SENSOR:
If the shorted sensor fault is displayed, the sensor in the
position reported was originally detected, but has since
shorted. The boiler will shut down on any SHORTED sensor
except the OUSTSIDE AIR sensor.
AIR SWITCH:
If the IGNITION control closes its blower relay, the control
does not see the PILOT relay close within (2) minutes, and the
AIR PRESSURE switch is made, this message will be
displayed. This alarm protects the boiler from freeze ups being
caused by a blower bringing in cold outside air with no fire.
CALL SERVICE:
If the H-Net control closes the last interlock string entering the
ignition control and the ignition control never closes its
Blower Relay, the H-Net control will wait 2 minutes. The H-
Net control will then retry for the duration of the local pump
post purge time and then retry the ignition sequence. During
this time ―retry strt‖ will be displayed in the status screen.
After (5) attempts the H-Net control will lock out and display
call service.
HeatNet V3 2.x
Page 103