A.O. Smith TWI 35-200 Installation, User And Service Manual page 46

c
46
Fig. Example parallel venting system
Refer to the table for the correct pipe dimensions of the C13 or a C33 parallel venting
systems.
Description
Diameter flue discharge/
air inlet
Maximum length air inlet
Maximum length flue gas outlet m
L 45°-bend
equivalent
L 90°-bend
equivalent
Caution
Always make sure the installation is in compliance with the requirements stated in this
table.
Caution
Use a special adapter box to convert the concentric connection on the water heater to a
parallel connection. This adapter box converts the 80/125 mm to two times 80 mm. This
adapter (0312209) can be ordered at your supplier or wholesaler. The use of a different
adapter box may cause the water heater to malfunction.
Calculate the maximum length of the air inlet and the flue gas outlet seperately:
1. Sum the lengths of the different pipe sections without bends. Ignore the length of
the adaptor box.
2. Sum the lengths of the bends. Ignore the bend in the adapter box:
- Sum L
equivalent
- Sum L
equivalent
5. Sum the lengths of the pipe sections and the lengths of the bends to calculate the
overall length of the air inlet and the flue gas outlet.
6. Adjust the length of the air inlet and/or the flue gas outlet when the overall length
exceeds the maximum length as stated in the table.
Unit
mm/mm
m
m
m
for each 45° bend.
for each 90° bend.
Installation, Maintenance and Service part
TWI 35–200
TWI 45–200
2 x 80
50
50
1,1
3,9