PV20a / PV30a pellet burner
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DK9902A1 www.pelltech.eu
PRE-BURN
The purpose of preburn mode is to fully ignite the pellets that were loaded for
ignition. Pre burn has 1-4 cycles (PAR 42) of 30-80seconds (PAR 41) each. No fuel
is added during the first cycle but ½ a rot of feeder auger is added between the
following feeder. During the pre-burn cycle the fan continues to work at the same
rps as in ignition mode (PAR8).
BURNING
This is main operation status in burner operation.Burner can operate on 11
different power levels. There is 6 main power levels, which can be selected and
adjusted and 5 virtual power levels between main levels that can't be adjusted or
selected. For every power level fan speed is fixed in parameters 1...6. The fan
speed for virtual levels are calculated as average from previous and next main
level speed. External auger is holding permanent fuel level in the feeder tube
during BURNING state. The auger is controlled by fuel level sensor in following
manner:
External auger is started after level sensor does not recognize fuel in
burner and internal feeder has done 2 rotations.
External auger is stopped when level sensor recognize fuel in burner for
more than 1s.
Pellet level in vertical feeder tube is detected by optical fuel level sensor. Fuel is
detected when pellets interrupt optical link between sensor pair. It is very
important that these optical sensors get cleaned routinely. If not, the pellet dust
will trick the sensors into thinking pellets are present in the feed tube when they
are not and you will get LEVEL ERROR
and NO FLAME errors. Burner will enter
level detection fault condition in following cases:
1.
Fuel loading timeout (no signal for specified period of time)
2.
Fuel unloading timeout (signal lasts longer than specified period of time)
HOLD FLAME
“Hold flame” mode purpose is avoid burner start-up procedures when BURNING
cycle is much longer than WAITING status. In HOLD FLAME mode, minimum fuel
and air amount is delivered into burning chamber. HOLD FLAME mode can be
switched from burner main menu to ON, OFF or AUTO. When HOLD FLAME is
selected as AUTO then burner will turn the mode on or off depending of WAITING
time:
- If WAITING (time between END BLOW and thermostat ON) is shorter than set
PAR11, then HOLD FLAME mode is switched on.
- if HOLD FLAME is longer than set in PAR12, HOLD FLAME mode is turned off.
AUTO status lasts 1 hour and ends with END BURN cycle. In HOLD FLAMEt cycle,
burner is fed pellets every 127 seconds and air is blowed as set in PAR10.
END BURN
Boiler has reached an estimated temperature and boiler thermostat has switched
off. In the END BURN mode all fuel inside the burning chamber and feeder tube is
burned - no more fuel is added from external auger. The feeder auger and fan
continue working as in previous mode (HOLD FLAME or BURNING).
END BLOW
In END BLOW mode only the fan keeps working PAR9 until all the pellet coals are
burned out. This mode lasts until no flame is recognized for one minute then the
burner returns to WAITING mode until boilers thermostat switches on.
NO PELLETS
Level sensor does not detect pellets in 5 or 20 minutes after LOADING.
Level sensor does not detect pellets in 4 minutes at BURNING time.
NO FLAME
There is no flame in the burner more than 120 seconds during BURNING.
FLAME ERROR
Flame doesn’t disappear in END BLOW TIME set in PAR27.
OVERHEAT
Temperature in the burner has reached temperature set in PAR43 and burner
turned itself off.
IGN.ERROR
Flame is not recognized after ignition cycle.
