25
CL3
Series
3.0
Installation
•
General Venting Requirements
General Venting Requirements
The venting system for CL3 series
heaters may terminate horizontally through a sidewall or vertically
through the roof, and may be individually or commonly vented. Configuration of the vent termination
determines the category type. All model heaters must be installed in accordance with the
requirements of this section, as well as the requirements of its category determination, as described
in this manual. To determine your applications category type, review “Vertical Venting (Category I)”
and “Horizontal Venting (Category III)” sections of this manual.
All CL3 Series
Model Requirements:
• Exhaust vent pipe must be 4 inch nominal size.
• Use vent pipe material that is corrosion-resistant galvanized steel of a thickness that meets the
National Fuel Gas Code.
• Do not exceed a maximum vent length of 20 feet.
• Maintain a minimum vent length of 3 feet.
• Maintain a minimum of 12 inches of straight pipe from the flue outlet before any directional
changes are made in the venting system.
• Have all vent pipe seams or connectors sealed with high temperature silicone sealant approved
for at least 550°F (field supplied) and fastened together with at least three (3) corrosion resistant
sheet metal screws (field supplied).
• Maintain a 6 inch clearance around all single wall vent pipe from any combustible materials. For
double-wall type B vent or Duravent PVP venting, follow the vent manufacturer’s clearances to
combustibles.
• The equivalent length for a 4 inch 90° elbow is 5 feet.
• Avoid using more than two 90° directional changes in the venting system.
• Suspend and secure all horizontal runs in a manner consistent with local codes and in such a way
that the vent system is supported to prevent sagging.
• Vent termination must maintain a minimum distance of 6 feet from any mechanical air supply
inlet.
• The vent terminal must be installed to prevent any blockage by snow and protect building
material from degradation by flue gases.
• Consult NFPA ANSI Z223.1 Gas Vent Termination criteria for vents that terminate on a roof pitch
that exceeds 9:12.
•
Canada:
Vents must terminate a minimum of 3 feet from a window or door that may be opened,
and a non-mechanical air supply inlet or combustion air inlet into the building.
