IBC EBX Series, Installation And Operation Manual, Page: 59 / 68

11.2.2 Miscellaneous issues
Miscellaneous issues
Issue Diagnosis Fix
‘Ghost’ call
for heat. Triac or ‘Power-
robbing’ thermostat
sending current to
boiler. Remove CN2 connections from boiler to confirm that stray
voltage, or current induced in thermostat wiring, is source
of nuisance signal. Replace the Power Robbing
thermostat or isolate the thermostat with a relay.
11.2.3 Cycling issues
Cycling issues
Issue Diagnosis Fix
Rapid
Cycling Incorrect settings or defective
thermostat. Check operation. Refer to manufacturer’s instructions.
Check setting with ammeter.
Air in system or marginal water
flow. Bleed/purge system as required. Confirm temp rise in
the heat exchanger.
Low water flow due to
improper piping. Review pressure drop of boiler piping.
Low water flow due to
restrictions in water pipe. Check temperature differential across zone/heat
exchanger.
Low radiation. Check actual amount of radiation per zone and refer to
manufacturer’s rating tables.
Appliance Oversized. Check load calculation vs. minimum boiler output.
Improperly set or defective
controls. Check operation with ohmmeter/voltmeter.
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11.2.2 Miscellaneous issues