Bosch Greentherm T9800 SEC 199 Installation And Operating Instructions Manual page 25

4.6.4 Recommended Vent Configuration Examples
Below are approved examples of vertical and horizontal venting
installations.
NOTICE: Using a single pipe vent in cold
climates puts the water heater at risk of
freezing, as negative air pressure is common
in buildings during cold weather. This
situation will pull cold air through the heat
exchanger and can lead to damage and a
water leak and is not covered by the
product's warranty. In the event of negative
air pressure causing back drafting contact
Bosch for information.
Fig. 12 Horizontal venting system (concentric vent)
[1] Exhaust
[2] Air intake
[3] Concentric Vent kit
[4] Exhaust pipe
[5] Air Intake pipe
[LA] Minimum 1"
Greentherm T9800 SE 160/199 | SEC 199
Fig. 13 Vertical venting system
[1] Exhaust
[2] Intake
[A] 12 inches (305 mm) (18 in. for Canada) above maximum
snow level or at least 24 inches (610 mm), whichever is
greater.
[B] 12 inches (305 mm)
[C] 12 inches (305 mm) minimum above air intake opening
A
Fig. 14 Horizontal parallel venting system (twin pipe)
[A] 3ft minimum
Vent terminals are at the same height.
Installation instructions | 25
6720816815-37.1V
6 720 816 815 (2018/08)