Viessmann Vitocrossal 300 CU3A Installation Instructions Manual page 4

Table of Contents
Direct Venting
(Two-pipe System)
4
CU3A Venting Systems Installation
Exhaust Vent/Air Intake Requirements.........................24
General requirements..............................................24
Combustion Air Supply...........................................24
General Installation Information...................................25
Installation steps (outline).......................................25
Exhaust and combustion air piping material...............25
Approved materials for two-pipe system.................26
Vent Requirements - Stainless Steel............................27
Additional requirements for stainless steel vent pipe
material................................................................27
Exhaust vent/air intake connection to boiler..............27
Combustion air intake pipe......................................27
Vent system manufacturers.....................................27
Maximum equivalent length
(horizontally or vertically vented)..............................28
Component Parts of the Venting System - Stainless
Steel........................................................................29
Exhaust vent termination options (vertical installation)..29
Other exhaust vent termination options
(horizontal installation)............................................29
Vent Requirements - CPVC........................................30
Additional requirements for UL/ULC-listed
CPVC vent pipe material.........................................30
Exhaust Vent/Air Intake Connection To Boiler............30
Vent and Air Intake Pipe Starter Adaptors - CPVC.........31
Requirements for UL/ULC Listed Rigid PP(s)
Vent Pipe Material.....................................................32
Vent system manufacturers.....................................32
Vent and Air Intake Pipe Starter Adaptors - PP(s)..........33
Side Wall Vent Termination - Stainless Steel,
CPVC or PP(s)..........................................................34
Vent Length Requirements.........................................35
Maximum vent/air intake pipe length - horizontal........35
Maximum allowable vent length - horizontal..............35
Flashing and storm collar installation........................35
Maximum vent/air intake pipe length - vertical...........36
Maximum allowable vent length - vertical..................36
Flashing and storm collar installation........................36
Maximum vent/air intake pipe length -
horizontal/vertical (hybrid system)............................37
Maximum allowable vent length - vertical exhaust/
horizontal air intake (hybrid)....................................37
Flashing and storm collar installation........................37
Standard long sweep elbows...................................38
Standard long sweep elbows (for CPVC pipe only).....38
Flue Vent Termination Requirements.........................40
Equivalent vent length calculation example................40
Multiple boiler installations (vertical flue termination)..40
Multiple boiler installations (horizontal flue termination)..40
Component Parts of the PP(s) Venting System.............41
Vertical pipe system...............................................41
Horizontal pipe system............................................42
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