www.desatech.com 113101-01C2WARNING: Improper installation, adjustment, altera-tion, service or maintenance can cause injury or prop-erty damage. Refer to this manual for correct installationand operational procedures. For assistance or addi-tional information consult a qualified installer, serviceagency or the gas supplier.WARNING: This appliance is for installation only in asolid-fuel burning masonry or UL127 factory-built fire-place or in a listed ventless firebox enclosure. It is de-sign-certified for these installations in accordance withANSI Z21.11.2. Exception: Do not install this appliancein a factory-built fireplace that includes instructionsstating it has not been tested or should not be used withunvented gas logs.WARNING: This is an unvented gas-fired heater. It usesair (oxygen) from the room in which it is installed. Provi-sions for adequate combustion and ventilation air mustbe provided. Refer to Air for Combustion and Ventilationsection on page 5 of this manual.This appliance may be installed in an aftermarket,* per-manently located, manufactured (mobile) home, wherenot prohibited by local codes.This appliance is only for use with the type of gas indi-cated on the rating plate. This appliance is not convert-ible for use with other gases.* Aftermarket: Completion of sale, not for purpose of resale, from the manufacturerTABLE OF CONTENTSSafety Information ............................................... 3Product Identification ........................................... 4Local Codes ........................................................ 5Unpacking ........................................................... 5Product Features ................................................. 5Air For Combustion and Ventilation ..................... 5Installation ........................................................... 8Operating Heater ............................................... 18Inspecting Burners ............................................ 22Cleaning and Maintenance ................................ 23Technical Service .............................................. 24Service Hints ..................................................... 24Replacement Parts ............................................ 24Troubleshooting ................................................. 25Optional Positioning of Thermostat Sensing Bulb ... 29Specifications .................................................... 30Accessories ....................................................... 31Parts Central ..................................................... 31Illustrated Parts Breakdown and Parts List ....... 32Warranty Information ...........................Back Cover