Atmos
Heating Systems
Installation and user manual EN_FMT
23
CHAPTER 6. BURNER STATES / MONITORING
6.1. Burner states
6.1.1. Rest state
Fan off - Gas valve off - Igniter off - Ionisation off
During the rest state, a check is made to see if there is burner
demand.
If a false flame signal is detected during the rest state for
more than 5 seconds, the Manager locks. If the glow plug
counter is too high (too many Starts), the regulation blocks the
burner demand.
If there is burner demand and no blocking, the system will go
over to purging/preheating.
6.1.2. Purging/Prestart
Fan off - Gas valve off - Igniter off - Ionisation off
The fan is switched on at the desired purging speed. The glow
plug is switched on at the same time as the fan.
After a few seconds, the fan goes from purging speed to the
faster ignition speed.
If a false flame signal is detected during purging, the
regulation locks.
If this lock is present for more than 5 seconds, the regulation
locks with ‘8’:
6.1.3. Ignition
Fan on - Gas valve on - Igniter on/off - Ionisation off/on
The fan is running at the ignition speed.
The gas valve is activated.
The Glow plug will be switched off as soon as an ionisation
signal is measured.
If there is no ionisation at the end of the safety time, a new
attempt at ignition will be made if this was not the last
permitted attempt at starting. Here, there will first be post-
ignition failure ventilation see 8.5.
If there is ionisation at the end of the safety time, the system
continues with operation:
6.1.4. Operation
Fan off - Gas valve off - Igniter off - Ionisation on
The fan is running at the required modulation speed.
If the ionisation fails, a restart is made, providing this is not
the third time within the burner demand. If this is the third
time, the Manager will lock.
The restart runs through post-ventilation purge, see 8.5.
If the burner demand ends, the system goes to post-
ventilation purge, see 8.5.
6.1.5. Post-ventilation
Fan on - Gas valve off - Igniter off - Ionisation off
The fan runs at the last demanded speed if the post-
ventilation is running at the end of the burner demand and in
all other cases at the highest speed.
If a false flame signal is detected during purging, the
regulation locks.
If this lock is present for more than 5 seconds, the regulation
locks with ‘?’:
With end of post-ventilation purging after the end of the burner
demand, a start test is run through:
6.1.6. Functional locking
Fan on/off - Gas valve off - Igniter off - Ionisation off - Alarm
contact on
During functional locking, the pump is on the central heating
circuit.
At the beginning of the interlock, in the fault table is updated
With some instances of interlock, the fan will post-ventilate for
1 minute at 50% of the maximum speed.
6.2. Monitoring
6.2.1. Monitoring the pump circulation
The pump is switched off for 3 seconds for each burner start.
At the same time, the purging/prestart time starts. The static
pressure is measured. After this, the pump is switched to a
high speed. The purging time starts as soon as the pump
speed has reached the desired value. At the end of the
purging/prestart time, the active pump pressure is measured.
If the difference between the active and the static pump
pressure is less than 0.05 bar, the regulation locks and goes
to the pump test program.
If the difference is more than 0.54 bar, the regulation locks
and goes to the pump test program.
If the difference is between 0.05 and 0.54 bar, the ignition
time starts.
When the pump is switched to the low state during ignition,
the pressure increase monitoring is switched off.
After the ignition time, the flow monitoring is realised by the
flow/return sensor.
If the temperature rise is large enough, the pump modulation
is released.
If the pressure changes afterwards by more than ± 0.1 bar (±
0,27 bar with changing pump speed) within 4 seconds, the
regulation will block and switch over to the pump test
program.
With switching over from central heating to hot water during
operation, the pressure fluctuation detection is defeated for 16
seconds.
6.2.2. Pump program
If the temperature difference between flow and return is
greater than 30°C, the pump switches to a high speed. When
the temperature difference drops below 10°C again, the pump
switches back to a low speed.
If the pump is on for a HWS demand with a Combi-unit or for
cylinder heat demand, the pump is continuously at high.
6.2.3. Pump test program
The pump is switched off for 15 seconds and high for 15
seconds. The display shows ‘P’.
The initial pressure is measured before the pump is switched
on. The test pressure is measured 3 seconds after the pump
is switched on. If the difference between these two pressures
is greater than 0.20 bar and less than 0.54 bar, the pump test
is finished.
