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VENTED DECORATIVE GAS LOG HEATER OWNER’S OPERATION AND INSTALLATION MANUAL MVO24VNA, MVO24VPA, MVO18VNA AND MVO18VPA WARNING: If the information in this manual is not fol- lowed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.
WARNING: Improper installation, adjustment, altera- tion, service or maintenance can cause injury or prop- erty damage. Refer to this manual for correct installation and operational procedures. For assistance or addi- tional information consult a qualified installer, service agency or the gas supplier. WARNING: This appliance is for installation only in a solid-fuel burning masonry or UL127 factory-built fireplace, constructed of noncombustible material and...
SAFETy INFORMATION WARNING: Any change to this log set or its controls can WARNING: This product con- be dangerous. tains and/or generates chemicals known to the State of California WARNING: This appliance to cause cancer or birth defects is equipped for (natural or pro- or other reproductive harm.
7. You must operate this log set with fireplace screen SAFETy INFORMATION in place and fully closed. Unless provided by Continued other means, screens shall have openings for introduction of combustion air. You must operate this appliance 8. If fireplace has glass doors, never operate with with a fireplace screen in place.
PRODUCT INSTALLATION IDENTIFICATION WARNING: A qualified ser- vice person must install heater. WARNING: Failure to position Follow all local codes. the parts in accordance with these diagrams or failure to use only WARNING: Before installing parts specifically approved with in a solid fuel burning fireplace, this appliance may result in prop- the chimney flue and firebox erty damage or personal injury.
Observe the smoke and be sure the vent is properly INSTALLATION drawing it up the chimney. If the smoke spills out Continued into the room, extinguish the flame and remove any CHECK GAS TYPE obstruction until proper venting is achieved. Use the correct gas type (natural or propane/LP) for The chimney flue damper must be fixed open to pro- your unit.
INSTALLATION CAUTION: Never connect Continued propane/LP unit directly to the Use screws provided to attach bracket to valve propane/LP supply. This unit re- bracket as shown in Figure 5, page 6. quires an external regulator (not Follow installation instructions included with supplied).
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INSTALLATION CSA Design-Certified Equipment Shutoff Continued Valve with 1/8" NPT Tap* CAUTION: Use only new, black Natural iron or steel pipe. Internally-tinned From Gas Approved Flexible Meter (5" W.C.** copper tubing may be used in Gas Hose (If to 10.5" W.C. certain areas.
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INSTALLATION Equipment Shutoff Valve Continued 3. Pressurize supply piping system by either opening propane/LP supply tank valve for Gas Meter propane/LP gas or opening main gas valve located on or near gas meter for natural gas or using compressed air. 4.
D. Do not use this appliance if any part has been INSTALLATION under water. Immediately call a qualified Continued service technician to inspect the appliance and 3. When unit is lit, check flames for random appear- to replace any part of the control system and ance and ember bed glowing red-orange in color any gas control which has been under water.
Appliances for Installation in Solid Fuel Burning Instructions on page 10. Fireplaces by OMNI Test Laboratories. After lighting, let pilot flame burn for about MVO18VNA AND MVO24VNA one minute. Turn control knob to ON posi- • Variable Rating: 36,000/53,000 Btu/hr tion. Adjust flame adjustment knob anywhere •...
If burner flame pattern is incorrect, as shown in INSPECTING bURNERS Figure 18. Check pilot flame pattern and burner flame pat- • turn appliance off (see To Turn Off Gas to Ap- terns often. pliance, page 11 ) PILOT FLAME PATTERN •...
TROUbLESHOOTING WARNING: Turn off appliance and let cool before servicing. Only a qualified service person should service and repair heater. CAUTION: Never use a wire, needle or similar object to clean ODS/pilot. This can damage ODS pilot unit. Note: All troubleshooting items are listed in order of operation. OBSERVED PROBLEM POSSIBLE CAUSE REMEDY...
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TROUbLESHOOTING Continued OBSERVED PROBLEM POSSIBLE CAUSE REMEDY ODS/pilot lights but flame goes 1. Control knob not fully 1. Press in control knob fully out when control knob is re- pressed in leased 2. Control knob not pressed in 2. After ODS/pilot lights, keep long enough control knob pressed in for 30 seconds...
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TROUbLESHOOTING Continued OBSERVED PROBLEM POSSIBLE CAUSE REMEDY Dark orange flame in burner dur- 1. Not enough air 1. Check burner(s) for dirt ing burner combustion and debris. If found, clean burner(s) (see Cleaning and Maintenance, page 12) 2. Gas regulator defective 2.
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TROUbLESHOOTING Continued WARNING: If you smell gas • Shut off gas supply. • Do not try to light any appliance. • Do not touch any electrical switch; do not use any phone in your building. • Immediately call your gas supplier from a neighbor’s phone. Fol- low the gas supplier’s instructions.
SERVICE HINTS ACCESSORIES Purchase these appliances from your local dealer. When Gas Pressure is Too Low If they can not supply these accessories, call DESA • pilot will not stay lit at 1-866-672-6040 for referral information. You • burners will have delayed ignition can also write to the address listed on the back •...
ILLUSTRATED PARTS bREAkDOWN MODELS MVO24VNA, MVO24VPA, MVO18VNA AND MVO18VPA www.desatech.com 114924-01D...
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PARTS LIST This list contains replaceable parts used in your heater. When ordering parts, follow the instructions listed under Replacement Parts on page 17 of this manual. NO. PART NO. DESCRIPTION qTY. 111793-01 Grate • • 111808-02 Grate • • 111817-02 Flexible Tube •...
WARRANTy INFORMATION kEEP THIS WARRANTy Model Serial No. Date Purchased Always specify model and serial numbers when communicating with the factory. We reserve the right to amend these specifications at any time without notice. The only warranty applicable is our standard written warranty.