Bosch 520PN Applications Manual page 60

18 | Installation instructions
Fig. 15 Horizontal venting system (single pipe penetration)
[1] Exhaust pipe
[2] Drain tee
[3] Intake pipe
[LA] Minimum 4"
WARNING:
▶ Single pipe penetration should be used in non-
freezing climates only and steps must be taken to
ensure that adequate combustion air is available to
the water heater at all times!
4.3.4 Vent connections
Attaching the exhaust and air inlet connection adaptors to the top of
the heater
▶ Attach the flue gas exhaust accessory to the top of the unit fig. 16
(position 1) using the 4 screws and gasket provided, and fully insert
vent pipe into the accessory. If using 4" venting, a 3" to 4" increaser
should be installed directly after this accessory.
NOTE: Vent pipe must be completely vertical when
inserting or blue gasket inside exhaust accessory can
become displaced. Exhaust accessory can be removed
with vent pipe attached to check gasket position.
Fig. 16 Exhaust connection
6 720 644 887 (2013/02)
▶ Attach the combustion air inlet accessory to the top of the unit fig. 17
(position 2) using the 3 screws and gasket provided, and install 3" air
intake pipe over the accessory.
Fig. 17 Inlet connection
NOTE: The combustion air accessory can be installed on
the top right or on the top left side of the heater. The
combustion air inlet that is not used must be kept sealed.
4.3.5 Connecting the condensate water drain
WARNING:
▶ Failure to properly install condensate drain can
damage the appliance and will void the warranty.
WARNING:
▶ Do not install condensate drain tubing in areas where
it may freeze.
The condensate must be disposed of in accordance with
local codes.
See chapter 4.11 "Filling the condensate trap".
Use materials approved by the authority having
jurisdiction. In the absence of other authority, PVC, and
CPVC pipe must comply with ASTM D1785, F441
orD2665. Cement and primer must comply with ASTM
D2564 or F493. For Canada, use CSA or ULC certified
PVC or CPVC pipe, fittings and cement, see table 5.
Appliance condensate drain installation
The appliance comes equipped with an internal condensate drain and
siphon. This drains condensation formed in the secondary heat
exchanger. Piping must be installed under the condensate drain outlet
on the water heater and piped for disposal in accordance with local
codes.
C 1210 ES/ESC