Vertical Venting Layouts; Layout Of Vertical Vent System With Accessories - Viessmann Vitocrossal 300 CU3A Installation Instructions Manual

Vertical Vent Installation (Coaxial)

Vertical Venting Layouts

Legend
A Combustion air
B Boiler flue gas termination
C Coaxial adaptor (Centrotherm shown)
D 90° elbow
E Straight pipe (long)
F Straight pipe (short)
G 45° elbow
H Roof flashing and storm collar
I Roof coaxial termination
J Increaser (if required)
Note: Depending on the selected vent manufacturer,
a service clearance of 36 in. may be required.
Consult the vent manufacturer if using two-pipe
to coaxial adaptor directly at the back of the boiler.
18
CU3A Venting Systems Installation
Layout of Vertical Vent systems with accessories
Select from the vertical vent components below as required.
Do not exceed maximum equivalent vent length,
see page 17).
Coaxial adaptor installation
Note: This installation procedure is only required for the
CU3A 45, 57 and not for the CU3A 26, 35.
1. Remove the inspection port bolt 1 from the top of
the vent connection (as shown).
2. Fully insert the coaxial adaptor into the boiler.
3. Mark the center of the inspection port on the adaptor.
4. Remove the coaxial adaptor from the boiler and drill a
f in. hole where marked.
5. Deburr the edges of the drilled hole.
6. Fully install the coaxial adaptor into the boiler and align
the inspection port hole to the coaxial adaptor hole.
7. Reinstall the inspection port bolt 1 and tighten bolt
to seal.
General vertical venting layout for vent systems,
Roof coaxial termination I.
Use other anchoring/support system components as
required.
IMPORTANT
Ensure that the venting system is properly supported; the
Vitocrossal 300 CU3A boilers are not designed to support
the weight of the venting system.
IMPORTANT
Vitocrossal 300 CU3A requires an adaptor to convert
to a coaxial system. Consult the vent manufacturer.
This adaptor must be ordered from Viessmann.