5-7
TROUBLESHOOTING
SL 35-199, SL 45-260 MODULATING GAS BOILERS
SYMPTOM
DIAGNOSIS
REMEDY
MAXIMUM IGNITION TRIALS
ERROR
Touch Screen Message
:
Error – Ignition Failure after 3
tries
Boiler has failed to ignite on 3
successive attempts. Boiler in
lockout for 1 hour, then repeats
3-try seq. Consult service
technician if error recurs.
No spark when igniting.
Igniter probe/flame
sensor disconnected.
Check that igniter lead is secure at the control
module and at the probe.
Manual gas shutoff is
closed or gas line not
fully purged.
Check for gas flow. Open manual gas shutoff
and reset boiler.
Gap between igniter
probe rods is too large
or too small.
Adjust ignitor probe rod gap as follows:
With Fenwal module – between 1/8th and
3/16th (3.2-4.7mm)
With Capable Controls ignition module – 3/16”
(5mm)
Spark, but no ignition.
Check spark module is sending power to gas valve
– close gas supply, then disconnect (black) electric
housing from face of gas valve, gently spread
plastic tabs to open, and look for 24vac voltage
between blue and brown wires during an ignition
cycle. Replace module if no current detected
Boiler ignites, but shuts
off at the end of the
ignition trial. Improperly
grounded pressure
vessel/burner or
unserviceable ignition
lead or spark module.
• Ensure pressure vessel is grounded.
• Check the igniter probe/flame sensor is
electrically isolated from the vessel, and its
ceramic insulator is intact.
• Replace ignition lead
• Replace spark module
HI LIMIT ERROR
Touch Screen Message:
Error – Water High-Limit
Exceeded
Water temperature exceeds hi-
limit. Boiler in hard lockout. Will
reset in 1 hour. Consult service
technician.
Defective or
disconnected hi-limit
switch.
• Check wiring to hi-limit switch and control
module.
• Check hi-limit switch. See
Section 5.2.5
.
VENT HI-LIMIT ERROR
Touch Screen Message:
Error - Vessel/Vent High-Limit
Exceeded *** Call for service!
Vent temperature has exceeded
the vent limit switch or the
upper vessel high limit has
been tripped. Boiler in lockout.
Consult service technician.
Indicates one or both
switches has tripped.
• Check wiring to ensure switches are properly
connected to control module.
• Check for evidence of any damage to vent
system and signs of excess heat near
switches.
• Push manual reset button(s), maintain
constant watch during boiler operation
to evaluate vent/cabinet temperatures at
maximum operating settings. Ensure no
unsafe condition exists, e.g. max flue temp.
or heat escapement at the burner flange.
Summary of Contents for SL 35-199
Page 71: ...SERVICE RECORD DATE LICENSED CONTRACTOR DESCRIPTION OF WORK DONE...
Page 72: ...NOTES...
Page 73: ...NOTES...
