INSTALLATION AND OPERATION INSTRUCTIONS
5-6
SL 30-175, SL 45-260 MODULATING GAS BOILERS
5.3 trouBlesHooting guide
SYMPTOM
DIAGNOSIS
REMEDY
AIRFLOW ERROR
LCD Screen Message:
Error – Insufficient Air Flow
Insufficient combustion airflow;
soft error; will retry in 5 minutes
Check fan operation
• Check lead is attached at fan.
• Cycle power off/on; listen for fan initialization.
if no action, focus your attention on the fan
itself.
Check for fouled
reference lines and air
sensor
• Check clear vinyl air pressure line for
presence of water. after disconnecting from
black air pressure sensor, blow clear
(do not
blow into sensor).
Check for exhaust re-
ingestion, or repeated power interruptions .
• Ensure condensate trap is not blocked.
• Go to Advanced Diagnostics and check
differential air pressure sensor (at rest and
with fan on). see
Section 5.2.3
.
Check achieved fan
power
in advanced diagnostics, during Pre-purge, Fan
Pressure (FP) should move close to required
Pressure (rP); if FP only 120-150 vs. rP of
[250 or 300], then check for actual vent system
blockage: (a) disconnect intake within boiler
case; (b) open burner then fan/gas valve looking
for debris.
Water noise in vent.
Excess condensate in
venting.
• Check condensate trap for obstructions.
Remove obstructions and refill condensate
trap with water.
• Check vent length, size and configuration.
WARNING
Never attempt to repair
the control module (circuit
board). If the control module
is defective, replace it
immediately.
5.3.1 Using Control Module Errors Displayed
Summary of Contents for SL 30-175
Page 76: ...NOTES...
