2
guarding the exposed flue pipe where a potential danger is
presented.
5. The stove must not be operated with the mica-viewing panel
cracked or damaged.
6. The mica-viewing panel may require light cleaning
occasionally depending upon the continuous running time of
the stove.
7. The stove must be securely fastened down so that it can resist
impact or collision and it must be level in both directions.
2
2
-
-
0
0
O
O
U
U
T
T
L
L
I
I
N
N
E
E
O
O
F
F
C
C
H
H
I
I
M
M
N
N
E
E
Y
Y
P
P
R
R
O
O
B
B
L
L
E
E
M
M
S
S
1. The fitting of any appliance, solid fuel, wood or oil burning,
requiring a naturally generated chimney vacuum, into a
traditional narrow boat creates specific problems, which are
mainly concerned with flues amongst other things.
2. Normally when fitting stoves into houses or bungalows
although there are many problems, generally if the chimney
comes out of the highest point of the property (normally the
ridge of the highest roof) stoves will work well in most normal
cases.
3. With boats the two major problems are -:
They move
And
By the nature of their shape, must have relatively low
chimneys.
4. Whilst on the move the boat will travel through a variety of
changing countryside which will have a dramatic effect on the
atmospherics at the chimney terminal.
5. An example of this would be the transition of a boat down
through a lock where the wind conditions at the outlet of the
chimney will change dramatically as the boat descends into the
lock to the lower water levels, severe down draught could
occur.
6. Great care must be followed with chimneys on boats and it is
critical to observe the following instructions.
7. To ensure satisfactory performance from the BUBBLE stove
chimneys must be capable of maintaining a constant steady
vacuum of not less than .04" Water Gauge when running on the
high fire position and not less than .02" Water gauge when
running on the low fire position
; at all times and in all
terminal conditions.
8. This obviously means that it is essential to fit a suitable anti
down draft device to the terminal of the chimney.
10. The chimney vacuum is directly proportional to the
following factors -:
10-1. The height of the chimney.
10-2. The resistance of the chimney. (Bends. terminals. etc.)
10-3. The cross sectional area of the chimney (diameter)
10-4. The Flue gas temperature.
10-5. The availability of replenishment air (ventilation)
10-6. The integrity of the chimney (does it leak)
11. The contents of the chimney are equal to a cylinder of hot
air which depending upon its temperature and volume wants to
move vertically, with some force.
12. Stopping it moving vertically are resistance such as-:
12-1. Smoothness of internal wall of chimney.
12-2. Chimney bends.
12-3. Chimney terminals.
12-4. Lack of ventilation. (Air going out must be replaced by
air coming in).
12-5. Atmospheric conditions at the chimney terminal that
could be affected by where the boat is moored.
IN SHORT -:
13-1 Hot air in large volumes = plenty of chimney pull.
(Vacuum)
13-2 Cold air in small volumes = little chimney pull.
13-3 Bends and chimney terminals create resistance to hot air
flow thus reducing potential maximum chimney vacuum.
14. Because it is not possible to use high chimneys it is critical
to observe the following instructions.
14-1. The chimney system must be designed so as to be easily
extendible.
14-2. The chimney can have a minimum inside diameter of
90mm.
14-3. Outside the boat, the chimney should be twin wall and
insulated to keep the flue gasses as hot as possible.
14-4. The chimney and stove must be adequately guarded to
prevent the risk of injury through burning.
15. When moored extend the chimney if you want the appliance
to be run at its maximum output, if you are happy with the
output of the stove running at up to setting 3, then it will not be
necessary to add the chimney extension.
16. The chimney terminal must be fitted with a terminal that
will resist down draughting in all terminal conditions.
16-1 MINIMUM HEIGHT FOR HIGH FIRE RUNNING IS 2.2
METER’S (long extension)
17. When cruising reduce the chimney height and turn the stove
down to match the reduced chimney height.
18. Do not cruise with the stove turned up on full output.
19. MINIMUM HEIGHT FOR LOW FIRE RUNNING IS 1.8
METERS. (Short extension)
20. When mooring pay particular attention to the
surroundings and remember that close objects such as high
buildings, trees or adjacent walls may well cause down or
up draughting.
Typical flue set ups can be seen in the illustrations FLUE
LAYOUT showing the flue pipe fitting into a standard cast iron
deck flange topped of with a traditional twin wall chimney,
terminating with a rotating cowl.
