Dunkirk Q95M-200 Modulating Condensing Boiler - Manual (Page 22)

22
STANDBY MODE - BOILER SEQUENCE DISPLAY
After display shows Stby for a brief period, first character shows boiler status, followed by boiler outlet water temp. If the burner is
being held off due to a soft lockout, the display alternates between showing “9” followed by boiler outlet water temp. and “b” followed
by the two-digit codes below. Soft lockout means the boiler will start again automatically if the condition is corrected or timed out.
Press [ RESET] button to restart boiler without waiting for timeouts below.
First
Digit
Other
Digits
Boiler Status
0
Actual (measured) outlet water temperature
Standby - no call for heat
1
Pre-purge (10 seconds) or Post-purge
(15 seconds)
2 Ignition
3 Burner on for CH heating
4 Burner on for DHW heating
5 Checking airflow before pre-purge
6
Burner off because temperature setting
has been reached
7
Pump on after CH heating cycle for run-
on of 10 seconds
8
Pump on after DHW heating cycle for
run-on of 30 seconds
H
Burner on, running in high fire mode
(manually set for test)
L
Burner on, running in low fire mode
(manually set for test)
First
Digit
Code
#
Boiler is in soft lockout when “9” or “b” shown. Reason for
boiler soft lockout is:
“9”
alternating with
“b”
_18 Outlet temp. too high (over 203°F). Burner off until outlet water
temp. drops 9°F below target temp.
_19 Return temp. too high (over 203°F). Burner off until both outlet
and return water temp. drops 9°F below target temp.
_24 Return temp. higher than supply temp. Burner off waiting for
correction.
_25 Outlet water temp. rose too quickly. Burner off 10 min. (burner
recycles, increasing wait 1 min. each attempt to max. 15 min.)
_26
External limit open, LWCO tripped or 3.5” press switch open on
limit wired in soft lockout (auto reset) circuit. Burner off for 2½
minutes.
_29 Blower signal not 0 when it should be. Burner off until signal
condition terminates.
_30
Temp. rise across boiler more than 100°F. Burner off for 2½
minute wait (plus 1 minute for each failed attempt, up to max. of
22 minutes each time).
_61 Air pressure switch does not open.
_65 Waiting for blower to start.
10 - USER INTERFACE QUICK REFERENCE