Desa H Owner's Operating And Installation Manual

Also see for H): OWNER'S OPERATION AND INSTALLATION MANUAL OWNER'S OPERATION AND INSTALLATION MANUAL

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Desa H Owner's Operating And Installation Manual Manual pdf 9 page image

108795-01F99For more information, visit www.desatech.comFor more information, visit www.desatech.comVENTING INSTALLATIONA B-type venting system must be connected to the appliance forventing to the outside of the building.The following section is provided as a guide to a standard B-typevent installation.Standing codes requirements concerning B-type vent installationsmay vary within your state, province or local codes jurisdiction.Therefore, it is recommended that you check with your localbuilding codes for specific requirements or in absence of localcodes, follow Section 7.0 of the current National Fuel Gas CodeANSI Z223.1/NFPA 54 and in Canada with CAN/CGA B149 forCategory I systems using double wall B-1 vent pipe.This gas appliance must be vented to the outdoors only and may notbe terminated into an attic space or into a chimney flue servicing asolid-fuel burning appliance.This appliance may be vented through a manufactured chimneysystem or a masonry chimney using a B-vent adapter or a chimneyliner system if all are listed, inspected and approved by local codesand/or building authorities.The examples shown in Figure 10 are typical of most B-ventinstallations and codes practices.Example 1: Shows the minimum allowable system height andlateral offset for a 60° degree or greater inclination. Code specifiesthat offsets at 60° degrees or greater are considered horizontal andmust follow the 75% percent rule for lateral to total vertical systemheight. Codes also allows only one offset in the total system whenat 60° degrees or greater. The total vertical height in this examplerepresents the minimum height of 8 feet and therefore the allowablelateral is 6 feet when the 75% percent rule applies. If the laterallength must exceed 75% then the system must be sized in accor-dance with the Category I venting tables.Example 2: Shows a multiple offset each at 45° degrees ofinclination. Multiple offsets are permitted if they do not exceed 60°degrees of inclination. The total lengths of the two offsets are notrequired to meet the 75% percent allowable rule.Example 3: Shows a single offset at 45° degrees of inclination andtherefore the lateral length at 10 feet of offset does not have to meetthe 75% percent rule.In each case the offsets must be supported and firestops must bepositioned wherever the vent must pass through a sub-floor, ceilingjoist or an attic overhang. The vent pipe must terminate verticallyinto a listed type vent cap and extend a sufficient height through anapproved roof flashing, roof jack or a roof thimble. At all points thelisted clearances must be maintained.MaintainListedClearance12' Min.12' Min. 45°45°6'8'12' Min.60° 45°PositionFirestopPositionFirestopPositionFirestopListedVent CapListedVent CapListedVent CapMaintainListedClearanceMaintainListedClearanceMaintainListedClearanceMaintainListedClearanceMaintainListedClearanceSupport EachLateral AtLeast EverySix (6) FeetMaintainListedClearance10'EXAMPLE 3EXAMPLE 2EXAMPLE 1Figure 10 - Typical B-Vent ConfigurationVENTING INSTALLATION