26
Gasifying boilers VIGAS
VIGAS 18 DPA, VIGAS 26 DPA
11.7 BOILER CLEANING
Wood characteristic table
Wood
Fuel efficiency
[MJ/kg]
20% humidity
Fuel efficiency
[MJ/kg]
25% humidity
Hardness *
weight [kg/m
3
]
25% humidity
Poplar
12,9
12,3
1
530
Fir
15,9
14,0
1
575
Spurce
15,3
13,1
1
575
Willow
16,9
12,8
1
665
Pine
18,4
13,6
1
680
Alder
16,7
12,9
2
640
Birch
15
13,5
2
780
Maple
15
13,6
4
660
Beech
15,5
12,5
4
865
Ashen
15,7
12,7
4
865
Locust
16,3
12,7
4
930
Oak
15,9
13,2
4,5
840
[kg/m
3
] = [kg/fm], fm – fullmeter, * (1 very soft...5 very hard)
Important information !!!
Use only recommended fuel.
Do not overload the boiler with fuel during mid-season period, to avoid tar production.
When refilling the boiler, make sure that fuel does not get between mounting and chimney flap. This
would stop chimney flap from proper closing.
It is important to lay wood properly, to allow proper closing of the upper door. Forced closing can
damage heatproof lining.
It is recommended that only person over 18 years, should operate the boiler.
Gasification chamber cleaning
It is necessary to remove tar from the gasification chamber once a week. It is recommended to burn it off
with the upper door and chimney flap open. If there is extra ash which did not fall through the nozzle
(pic. 3/9) into the fireclay combustion chamber, this should be removed from time to time. Fuel bunker will
increase to the original size and primary air flow through nozzle will be enhanced.
Optimal wood burning and keeping minimum temperature of the reverse water at 60°C will ensure that the
gasifying chamber and exchanger will only soot little. Using damp wood may cause water to condense on
the walls of the combustion chamber, which creates tar on the surface.
Exchanger cleaning
It is necessary to clean exchanger pipes once a month using the fire rake (round plate). Than remove ash
from lower part of combustion chamber through bottom door.
Recommendation:
If the exchanger is not cleaned regularly it will become clogged with tar. Do not use
solvents. The boiler must be cleaned whilst it is hot! Heat boiler to approx 80°C (without fan) through open
upper door and chimney flap. Then close the flap and door. Using gloves, carefully open exchanger cover.
Clean clogged pipes with relevant accessories. After cleaning, close exchanger cover and let the boiler
burn / gasify for approx. 5 hours at maximum performance, in order to get rid of any remaining tar. Avoid
this situation in the future.
WARNING: Boiler room area must be permanetly ventilated at maximum during cleaning time.
Combustion chamber cleaning
It is recommended to sweep out ash and dust that has fallen and settled in the combustion chamber once
every 3-5 days. When using pellets, clean the pellet burner once a month.
NOTICE !
Pellet burner is placed together with firebricks inside combustion chamber. Please take care for
burner to be cleaned and placed to its initial space.
Burner
Combustion
chamber
Humidity dependence period
( wood cuts)
Fir
SPURCE
Beech
Recommended humidity 20%
OAK
12
14
16
18
20
22
24
26
28
30
6
12
18
24
Number of months after cutting
h
u
m
id
it
y
[
%
]