UNVENTED (VENT-FREE) GAS LOG HEATEROWNER’S OPER ATION AND INSTALLATION MANUALDesign Dynamics Ventfree Models Also Design-Cer tified As Vented Deco rative Appli anc esSave this manual for future reference.WARNING: If the information in this manualis not followed exactly, a fire or explosionmay result causing property damage, per-sonal injury, or loss of life.— Do not store or use gasoline or otherflammable vapors and liquids in the vicinityof this or any other appliance.— WHAT TO DO IF YOU SMELL GAS• Do not try to light any appliance.• Do not touch any electrical switch; do notuse any phone in your building.• Immediately call your gas suppli er froma neighbor’s phone. Follow the gas sup-plier’s instruc tions.• If you cannot reach your gas supplier, callthe fire department.— Installation and service must be performedby a qualified installer, service agen cy, orthe gas supplier.WARNING: Improper installation, adjust-ment, alteration, service, or maintenancecan cause injury or property damage. Referto this manual for correct installation andoperational procedures. For assistanceor additional information consult a quali-fied installer, service agency, or the gassupplier.WARNING: This appliance is for instal-lation only in a solid-fuel burning masonryor UL127 factory-built fireplace, or in anapproved ventless firebox. It is design-certified for these installations in accor-dance with ANSI Z21.11.2. Exception: Donot install this appliance in a factory-builtfireplace that includes instructions statingit has not been tested or should not beused with unvented gas logs.WARNING: This is an unvented gas-fired heater. It uses air (oxy gen) from the room in which itis installed. Provi sions for ad e quate com bus tion and ven ti lation air must be provid ed. Referto Air for Combustion and Ven tila tion section on page 4 of this manual.This appliance may be installed in an aftermarket,* manufactured (mobile) home, where notpro hibit ed by local codes.This appliance is only for use with the type of gas indicated on the rating plate. This appli anceis not convertible for use with other gases.* Aftermarket: Completion of sale, not for purpose of resale, from the manufacturerWarning: This product must be installed by a Licensed Plumber or Gas Fitter when installedwithin The Commonwealth of Massachusetts.VF-24N-PDG, VF-24P-PDG,VF-18N-PDG, VF-18P-PDGVF-24N-BTB, VF-24P-BTB,VF-18N-BTB, VF-18P-BTBFor more information, visit www.desatech.com