16
VIII - TROUBLESHOOTING
Boiler Not Firing And:
Check For:
Step
Corrective Actions:
Control display blank
120 vac at terminals L1 and L2 of
line voltage strip?
1
NO - Check external line switch and fuse or breaker.
120 vac on both sides of fuse F1?
(Turn OFF external power to boiler
before removing cover.
1
NO - Turn off power to boiler and replace fuse if necessary.
Inspect boiler interior wiring to determine cause of fuse
opening.
Wiring correct, in good condition,
and securely attached?
1
Correct if needed. Replace any damaged wiring or
components. Replace control module if problem persists.
Display first digit shows 0; last
digits show 2 or 3-digit number
(boiler outlet water temp.)
Room thermostat and DHW
aquastat satisfied?
1
YES - Boiler off, no call for heat. Turn up thermostat or
aquastat. Boiler should start.
Thermostat or aquastat calling for
heat but boiler not firing.
1
Check voltage on both sides of low voltage fuse F3.
(Turn OFF external power before removing cover.) If
necessary, replace fuse. Determine reason for fuse failure
if possible.
2
Check/set boiler parameters 2 and 3. Make sure space
heat or DHW is turned on. Turn on if necessary.
3
Turn off power to boiler. Temporarily jumper low voltage
terminal strip terminals T1 and T2 or DHW T1 and
DHW T2. Retry. If boiler operates, check CH and DHW
thermostat and wiring. Replace if necessary. Remove
temporary jumper(s).
4
Turn off power to boiler. Check wiring against wiring
diagram; verify all wiring in good condition and secure.
5
replace wire harnesses and retry.
6
Replace control module.
Display first digit shows a number from 1 to 8; last digits show 2 or
3-digit number (boiler outlet water temp.)
1
Boiler in normal operating mode.
Display flashes “9,” then “b.” Last two digits show code number.
1
see
User Interface Quick Reference
and
Soft Lockout
Troubleshooting
in this manual for for more information
on the soft lockout code.
SOFT LOCKOUT
(Display flashes “9” and then “b” in first position; last two digits on steady (code))
Code
Reason For Soft Lockout
Corrective Actions
(pressing RESET should restart boiler immediately):
WARNING:
Electrical shock hazard. Turn off power to boiler when working with wiring or replacing any boiler component.
08
0.14” Pressure switch contacts open
1
Check pressure switch for proper operation. Replace pressure switch if moisture
has entered switch. Check venting for blockage. Clear if present.
18
High Limit Operation:
Burner off
until outlet water temp. drops below
180 °F
1
This should only happen when the heat demand is lower than the lowest firing rate
of the boiler, such as operation of a single, small zone. Check system for:
Verify boiler and system are full of water.
•
Make sure system does not have trapped air.
•
Inspect and verify system piping and components.
•
Verify piping agrees with boiler manual recommendations.
•
2
Use contact thermometer to check outlet water temp. Compare to temp. shown with
display in “INFO” mode (
“1”
in first digit). Replace return temp. sensor if results are
not close. Replace control module if sensor replacement doesn’t solve problem.
19
High Limit Operation:
Burner off
until return water temp. drops below
190 °F
1
Check system for:
Verify boiler and system are full of water.
•
Make sure system does not have trapped air.
•
Inspect and verify system piping and components.
•
Make sure water flow is not reversed or pipes crossed.
•
2
Use contact thermometer to check return water temp. Compare to temp. shown with
display in “INFO” mode (
“2”
in first digit). Replace return temp. sensor if results are
not close. Replace control module if sensor replacement doesn’t solve problem.
