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In Canada construct
all combustion
air and vent pipes for this unit of CSA or ULC certified
schedule-40
CPVC,
schedule-40
PVC,
PVC-DWV
or ABS-DWV
pipe and pipe cement.
SDR pipe is NOT approved
in Canada.
Combustion
air and vent piping connections
on boiler are sized for 2" pipe.
Any pipe size
change (to 3") must be made outside of the boiler casing in a vertical run of pipe to allow for
proper drainage
of vent condensate.
Due to potential
for flue gas temperatures
over 155°F,
the first five (5) feet of vent pipe must be CPVC, the remaining
vent pipe can be PVC.
If any
elbows are employed
within the first 5 feet of vent, they must be CPVC too. Two (2) - 30"
pieces of 2" CPVC pipe are furnished
with the boiler.
NOTE:
The transition
from 2" pipe to 3" pipe must be made in a vertical run.
Combustion
air and vent piping lengths;The
first 5 feet of "TOTAL EQUIVALENT
LENGTH"
of vent piping run must be CP¥C
it corresponds
as follows:
BOILER
2" PIPE
2" PIPE
3" PIPE
3" PIPE
SIZE
MINIMUM
MAXIMUM
MINIMUM
MAXIMUM
VENTING
VENTING
VENTING
VENTING
K90-100
2 FEET IN
LENGTH
+
4-90 °
ELBOWS
15 FEET IN
LENGTH
AND UP TO
4-90 °
ELBOWS
15 FEET IN
LENGTH
+
4-90 °
ELBOWS
80 FEET IN
LENGTH
AND UP TO
4-90 °
ELBOWS
2 FEET IN
20 FEET IN
20 FEET IN
100 FEET IN
K90-75
LENGTH
LENGTH
LENGTH
LENGTH
_L
+
AND UP TO
+
AND UP TO
K90-50
4-90°
4-90°
4-90°
4-90°
ELBOWS
ELBOWS
ELBOWS
ELBOWS
The length of pipe is counted from the boiler jacket (air intake pipe) or from vent tee (vent pipe).
For additional
elbows,
reduce the maximum
vent length as shown:
2" 90 degree elbow - 1 1/2 feet per additional
elbow.
3" 90 degree elbow - 3 feet per additional
elbow.
Example:
To add 2 additional
90 degree elbows to a 3"pipe for a K90-75 boiler.
Each elbow is 3 additional
feet per 90 degree elbow for a total of 6 feet.
(1 elbow @ 3
feet + 1 elbow @ 3 feet = 6 additional
feet of pipe) The total additional
pipe is then
subtracted
from the maximum allowable
pipe length to give the new maximum
length of
94 feet with 6, 90 degree elbows.
("TOTAL
EQUIVALENT
LENGTH":
Original
100
feet max. - 6 feet for 2 additional
elbows
= new 94 feet maximum
length).
.
Combustion
air and vent piping to be pitched back to boiler at minimum
¼ "per foot from
intake and vent terminals
so that all moisture
in combustion
air and vent piping drains to
boiler. Pipes must be pitched continuously
with no sags or low spots where moisture
can
accumulate
and block the flow of air or flue gas. Combustion
air and vent pipes must be
airtight and watertight.
21
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