IBC SL 35-199

5-11
TROUBLESHOOTING
SL 35-199, SL 45-260 MODULATING GAS BOILERS
5.3.5 Miscellaneous
SYMPTOM DIAGNOSIS REMEDY
FUMES AND HIGH HUMIDITY
Improperly installed
condensate trap
Refer to installation/operation instructions
Leak in vent piping Inspect using soap solution
Flue gas leak within boiler Visually inspect all mechanical connections
BOILER STUCK ON
INITIALIZE
Fan board failure Replace fan.
TOUCH SCREEN MESSAGE:
Unknown Error
Temperature sensor input
problem.
Test each temperature sensor for appropriate
readings and Replace defective temperature
sensor.
BOILER REMAINS IN
STANDBY DURING CALL FOR
RESET HEATING OR SET-
POINT (DHW OPERATION
WORKS AS NORMAL). (5
BUTTON CONTROLLER)
Boiler may be in Warm
Weather Shut-down.
InInstallerSetup/HeatLoadConguration
/CongureLoad(Heating)adjustSummer
Shutdown Temperature to a temperature
above that registered by outdoor sensor.
‘GHOST’ CALL FOR HEAT.
Triac or ‘Power-robbing’
thermostat sending current
to boiler.
Remove Therm. connections from boiler
toconrmthatstrayvoltage,orcurrent
induced in thermostat wiring, is source of
nuisance signal. Replace the Power Robbing
thermostat, isolate the thermostat with a relay
or install a properly sized resistor (consult the
thermostatmanufacturerrstthenIBCfor
instructions).
ERROR: WATER HIGH LIMIT /
LOW WATER CUT-OFF WON’T
CLEAR.
Boiler is in 1 hour safety
lockout.
Reset safety device and cycle boiler power off
and on to reset error.
DHW TAKING TOO LONG TO
HEAT.
Sensor may be under-
reading actual water temp.
Check sensor engagement; note well is 15cm
/ almost 6 inches deep and sensor must be
fully set to back. Check programmed settings
boiler temp set too close to the required DHW
temp
BOILER OUTPUT NOT
MODULATING UP TO
MAXIMUM DESPITE TARGET
NOT BEING REACHED.
Possible ow issue:
check for 35 or 40 degree
F temperature difference
between boiler supply and
return water temperatures
(evokes electronic fence).
Conrmthatprimarypumpisableto
overcome head loss of boiler and primary
looppipingattherequiredowrate.
PRIMARY PUMP RUNS BUT
LOAD PUMPS DO NOT.
Wiring not complete. Supply power to the PV/L and PV/N terminals
from the incoming power supply to the boiler.
(Factory wired on boilers with a factory
installed Touch Screen Controller)
PRIMARY PUMP RUNS
DURING PARALLEL-PIPED
DHW CALL.
Load denition as DHW. Re-deneDHWloadasDHWLoop2(5
button Controls) to turn off primary pump
during domestic hot water calls. On Touch
Screen Controllers set the boiler pump to off
in the Installer Set-up Menu.