5.5 Legend to time sequence diagrams
Phases:
00 Lockout phase
50 2nd safety time
01 Safety phase
52 Interval 2 (ti2)
10 Homerun
54 Low-fire position
12 Standby (stationary)
60 Operation 1 (stationary)
21 Shutoff valve ON (start release)
62 Operation 2
Low-fire position
22 Fan motor ON
70 Post-combustion time
24 Pre-purge position
72 Post-purge position
30 Pre-purge time (tv1)
74 Post-purge time (tn1)
32 Pre-purge time (tv)
76 Flue gas recirculation post-purge position
34 Pre-purge time (tv2) (flue gas recirculation
ARF)
78 Post-purge time (tn3)
36 Ignition position
79 Direct start
38 Pre-ignition (Z) ON
80 Valve proving evacuating time
40 Burner valve ON
81 Valve proving time atmospheric pressure
42 Ignition OFF
82 Valve proving filling time
44 Interval 1 (ti1)
83 Valve proving time gas pressure
Times:
t0
Post-purge lockout position
t78
Post-purge time 3 gas / oil (tn3)
t01 Max. time safety phase
t80
Valve proving evacuate time
t10 Min. time home run
t81
Valve proving time atmospheric pressure
t21 Min. time start release
t82
Valve proving filling time
t22 Fan running time
t83
Valve proving time gas pressure
t30 Pre-purge time part 1
tmn1
Min. time extraneous light test (5 s) after
skipping pre-purge
t34 Pre-purge time part 3
tmx1
Max. damper running time
t36 Min. ON time oil pump
tmx2
Max. time startup release
t38 Pre-ignition time gas/oil
tmx3
Max. time circulation heavy oil
t42 Pre-ignition time OFF
tn
Post-purge time
t44 Interval 1 gas/oil
TSA1 First safety time gas/oil
t62 Max. time low-fire
TSA2 Second safety time gas/oil
t70 Post-combustion time
tv
Pre-purge time gas/oil
t74 Post-purge time 1 gas / oil (tn1)
Abbreviations:
AL
Alarm
PV
Pilot valve
ARF
FGR = flue gas recirculation
R
Temperature or pressure controller ON
(in external)
CPI
Closed Position Indicator
RP
No-load position
DP
Pressure switch
SK
Safety loop (safety limit thermostat, water
shortage)
DW-DK Pressure valve proving
SP
Setpoint position
DWmin
Pressure switch-min
SR
Safety relay internal
DWmax Pressure switch-max
STB Safety limit thermostat
FS
Flame signal
SV
Shutoff valve
86 (114)
M4248 2316EN