Bard W18HB-A Installation Instructions Manual

Also see for W18HB-A: Installation instructions

Manual 2100-703Page 5 of 40Refer to the Maximum ESP of Operation table on page36.Design the duct work according to methods given bythe Air Conditioning Contractors of America (ACCA).When duct runs through unheated spaces, it shouldbe insulated with a minimum of 1" of insulation. Useinsulation with a vapor barrier on the outside of theinsulation. Flexible joints should be used to connectthe duct work to the equipment in order to keep thenoise transmission to a minimum.Models W18 and W24 are approved for 0" clearanceto the supply duct. For models W30 and W36, a 1/4"clearance to combustible material for the first 3' ofduct attached to the outlet air frame is required. SeeDucted Applications on page 7 and Figures 3A and 3B(pages 10 and 11) and Figure 4 (page 12) for furtherdetails.Ducts through the walls must be insulated and all jointstaped or sealed to prevent air or moisture entering thewall cavity.Some installations may not require any return air duct.A metallic return air grille is required with installationsnot requiring a return air duct. The spacing betweenlouvers on the grille shall not be larger than 5/8".Any grille that meets with 5/8" louver criteria may beused. It is recommended that Bard Return Air GrilleKit RG-2W through RG-5W or RFG-2W through RFG-5W be installed when no return duct is used. Contactdistributor or factory for ordering information. If using areturn air filter grille, filters must be of sufficient size toallow a maximum velocity of 400 fpm.NOTE: If no return air duct is used, applicableinstallation codes may limit this cabinet toinstallation only in a single story structure.FiltersA 1" throwaway filter is standard with each unit. Thefilter slides into position making it easy to service. Thisfilter can be serviced from the outside by removing thefilter access panel. A 1" washable filter and 2" pleatedfilter are also available as optional accessories. Theinternal filter brackets are adjustable to accommodatethe 2" filter by bending two tabs down on each side ofthe filter support bracket.Fresh Air IntakeAll units are built with fresh air inlet slots punched inthe service door.If the unit is equipped with a fresh air damperassembly, the assembly is shipped already attachedto the unit. The damper blade is locked in the closedposition. To allow the damper to operate, the maximumand minimum blade position stops must be installed(see Figure 1).Graphs found on pages 39 and 40 give approximatefresh air amounts based on the blade position stoplocation.All capacity, efficiency and cost of operationinformation is based upon the fresh air blank-off platein place and is recommended for maximum energyefficiency.The blank-off plate is available upon request from thefactory and is installed in place of the fresh air dampershipped with each unit.MIS-938FIGURE 1Fresh Air DamperBLADE IS LOCKED CLOSEDFOR SHIPPING