Boiler Manual - Weil-McLain

GV90+ gas-fired water boiler — Boiler ManualVent and air piping and boiler connectionsDIRECT EXHAUST & DIRECT VENTFigure 59 Boiler vent and air connectionsFollow termination instructions1. Read and follow all instructions for the terminationtype used before proceeding with this page.Installing vent and air piping1. Work from the boiler to vent or air termination. Donot exceed the lengths given in the previous pagesfor either the air or vent piping.a. Provide stainless pipe to PVC adapters obtainedfrom the stainless pipe manufacturer for connectionsat the boiler and at terminations, whenrequired.2. See Figure 59 for attaching vent (and air) pipes atthe boiler.3. Cut pipe to required lengths.4. Deburr inside and outside of pipe ends.5. Chamfer outside of each pipe end to ensure evencement distribution when joining.6. Clean all pipe ends and fittings. Dry thoroughly.7. Dry assemble entire vent or air piping to ensureproper fit before assembling any joint.8. For each joint:a. Handle fittings and pipes carefully to preventcontamination of surfaces.b. Apply primer liberally to both joint surfaces —pipe end and fitting socket.c. While primer is still damp, lightly apply approvedcement to both surfaces in a uniformcoating.d. Apply a second coat to both surfaces. Avoidusing too much cement on sockets to preventcement buildup inside.e. With cement still wet, insert pipe into fitting,twisting ¼ turn. Make sure pipe is fullyinserted.f. Wipe excess cement from joint. Check joint tobe sure a smooth bead of cement shows aroundthe entire joint.9. Maintain minimum clearance of C\zn inch betweenvent pipe and any combustible wall or material.10. Seal wall or floor penetration openings followinglocal code requirements.DIRECT EXHAUST ONLYDIRECT EXHAUST installations — airinlet opening protection: Obtain a birdscreen (sized for air inlet fitting) fromWeil-McLain. Insert the bird screen intothe air inlet fitting to prevent foreignobjects from entering the opening.AL294C vent pipe — If using AL294C stainless vent pipe,you must install an AL29-4C stainless vent starter at theboiler vent connection (and at the termination if usingthe Weil-McLain plate or the concentric termination).Use only the starter made by the vent pipe manufacturer.See Replacement parts section for available AL29-4Cstainless vent starters.1. PVC/ABS pipe — Clean and deburr inside and outside of otherboth ends of air and vent pipes. Chamfer boiler end of vent pipefor ease of insertion.The vent pipe end must be smooth and chamfered toprevent possible damage to sealing gasket in vent pipeadapter.2. Inspect vent adapter and air inlet fitting (above) — verify no obstructionsor foreign objects inside.3. Vent pipe• Loosen vent adapter clamp screw.• Measure 3½ inches from boiler end of vent pipe and make amark with felt-tip pen.• Apply small amount of silicon grease to boiler end of vent pipeto ease insertion.• Insert vent pipe into adapter to depth of felt tip pen mark.• Secure vent pipe by tightening the adapter clamp securely. Donot overtighten. The seal is accomplished with the internalgasket. The clamp is only to hold the pipe in place.Do not apply excessive force or bend the vent adapteror vent pipe when inserting. The adapter or seal couldbe damaged.4. Air pipe• Clean the outer surface of the boiler end of the air pipe.• Apply silicon sealant (Dow Corning 732 TM or equivalent) tothe outside end of the air pipe and to the inside of the air inletfitting.• Insert the air pipe into the air inlet fitting and give a 1/4 turnto ensure coverage. Support until the sealant has dried.48Part number 550-142-054/1211