Unigas R91, Installation Manual

Page: 32 / 120

PART III: OPERATION
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4.16 Starting the burner up by slowly increasing the output
The first burner lighting (at the beginnig of the cold season) must be performed in order to gradually
heat the boiler.For this reason, timers are installed inside the burner built-in or separate control panel, in
oder to control the low flame time. This function can be set by means of the CMF 4-positions switch
and three multiscale timers that can be set from 0.5 seconds to more than 10 hours.The burner per-
forms the normal ignition phase. Once it lights, the actuator starts opening (output increases) until the
limiter cam IV operates. The limiter cam is set 5° more than the low flame cam III.According to the CMF
switch position the settable functions are:
pos. 0: with the burner on, the actuator stops at its current position
pos. 1: burner drives to and stays at the high flame stage
pos. 2: burner drives to and stays at the low flame stage
pos. 3: burners is on and works in the modulating operation (TAB/RWF40)
pos.4: burner is on and the output increases very slowly according to the times set on the three timers
(KT1, KT2 and KT3).
KT1 Timer: it sets the actuator “On” time (usually 1 second)
KT2 Timer: it sets the actuator “Off” time
KT3 Timer: it sets the period of the actuator passing from the low flame to the high flame stage to the complete opening (90°)
Example:
Actuator “On” time = 1 second è Set the 0.1÷1 seconds scale and the cursor to 10 for the KT1 timer
Actuator “Off” time = 3 minutes è Set the 1÷10 minutes scale and the cursor to 3 for the KT2 timer
In this way, the actuator will move for 3° in 1 second period a will stay still for 3 minutes. To perform the 30°-90° stroke it will take 1
hour.
Set KT3 for about 1 hour time. After this time the function will be off. The burner will operate by means of the Siemens RWF40 modula-
tor (for fully-modulating burners) or by the ”High/Low” thermostat (for progressive burners).
SET THE TIMER FUNCTION KT1(MAR1) ACTUATOR “On” TIME
Set the 0.1÷1 seconds scale, Set cursor to 10
SET THE TIMER FUNCTION KT2 (MAR1) ACTUATOR “Off” TIME
ISet the 1÷10 minutes scale
CURSOR
”Off” TIME
ACTUATOR 30°-90° CYCLE TIME
1
1 min. 20 min.
2
2 min. 40 min.
3
3 min.
1 hour
4
4 min.
1.3hours
5
5 min.
1.6 hours
6
6 min.
2 hours
7
7 min.
2.16 hours
8
8 min.
2.3 hours
9
9 min.
3 hours
10
10 min.
3.3 hours
for higher times: set the 6÷60 minutes
CURSOR ”Off” TIME ACTUATOR 30°-90° CYCLE TIME
1 6 min. ~2 hours
2 11.4 min. ~3.8 hours
3 16.8 min. ~5.6 hours
4 22.2 min. ~7.4 hours
5 27.6 min. ~9.2 hours
6 33 min. 11 hours
SET THE TIMER FUNCTION KT2(MAR1): CYCLE OFF TIME AND BURNER MODULATION STARTING
ISET THE FULL-SCALE TIMES: set the 1÷10 hours scale
Set the cursor to the maximum reqired time (i.e. 1 = 1 hour, 2 = 2 hours, according to the actuator cycle total time set by the
KT1 and KT2 timers)
scale
cursor
MAR1 TIMER