Unvented Gas Log Heater or Vented Decorative Appliance Installation Instructions Model: NBST27 WARNINGS If the information in this manual is not followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life. – Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance. – WHAT TO DO IF YOU SMELL GAS • Do not try to light any appliance.
NBST27 Unvented Gas Log Set Important Safety Information..............................3 Codes..............................................................4 Getting Started......................................................5 Product Features and Specifications ................5 Gas Pressures.................................................5 Gas Specifications...........................................5 Ignition Controls...............................................5 Pilot/ODS............................
NBST27 Unvented Gas Log Set IMPORTANT SAFETY INFORMATION OWNER INSTALLER Please leave these instructions with the appliance. Please retain these instructions for future reference. IMPORTANT WARNING Read these instructions carefully before installing or trying to operate this vent-free gas heater. • Any change to this heater or its controls can be dangerous. • Improper installation or use of the heater can cause serious injury or death from fire, burns, explosion or carbon monoxide poisoning.
NBST27 Unvented Gas Log Set WARNING 19. During manufacturing, fabricating and shipping, various components of this appliance are treated with certain oils, films or bonding agents. These chemicals are not harmful but may produce annoying smoke and smells as they are burned off during the initial operation of the appliance; possibly causing headaches or eye or lung irritation. This is a normal and temporary occurrence.
WARNING GETTING STARTED - FEATURES and SPECIFICATIONS Gloves are recommended when handling ceramic fiber logs to prevent skin irritation from loose fibers. Logs are fragile - handle with care. Make sure you have received all parts: Check your packing list to verify that all listed parts have been received.
NBST27 Unvented Gas Log Set GENERAL INSTALLATION INFORMATION ADEQUATE COMBUSTION AND VENTILATION AIR This heater shall not be installed in a confined space or unusually tight construction unless provisions are provided for adequate combustion and ventilation air. The National Fuel Gas Code, (ANSI Z223.1/NFPA 54), defines a confined space as a space whose volume is less than 50 cubic feet per 1,000 BTU per hour (4.8 m3 per kw) of the aggregate input rating of all appliances installed in that space.
NBST27 Unvented Gas Log Set WARNING FIREPLACE and HEARTH DIMENSIONS This appliance is for installation only in a solid-fuel burning masonry or UL127 factory-built fireplace, vent free appliance, or in listed ventless firebox enclosure. It has been design certified for these installations. Exception: DO NOT install this appliance in a factory-built fireplace that includes instructions stating it has not been tested or should not be used with unvented gas logs.
WARNING NBST27 Unvented Gas Log Set CLEARANCE and HEIGHT REQUIREMENTS The dimensions shown in Figures 4 through 10 and defined in the fireplace manufacturer's instructions are minimum clearances to maintain when installing this heater. Left and right clearances are determined when facing the front of the heater. When heater is installed into a ventless firebox, minimum clearances, as specified by the ventless firebox manufacturer, must be met.
NBST27 Unvented Gas Log Set CLEARANCE and HEIGHT REQUIREMENTS Heat resistant material (minimum requirements) with wooden mantel or other combustible projection: To install the heater with a wooden mantel, shelf or other combustible projection above, first measure the heat resistant material shown in Figure 6, then refer to Table B. Figure 6 Measure Heat Resistant Material for Mantel Figure 7 Minimum Mantel Clearance with No Hood 10” or Less 28” Heat Resistant Material 12” Min.
NBST27 Unvented Gas Log Set FLOOR CLEARANCES The gas log heater must be installed at least 3/4" above any combustible flooring material, such as carpeting or tile, which is closer than 14" to the base of the fireplace. The minimum distance must be maintained from the top surface of carpeting, tile, etc.
NBST27 Unvented Gas Log Set WARNING WARNING FIREPLACE PREPARATION Before installing in a solid fuel burning fireplace, The chimney flue and firebox must be cleaned of soot, creosote, ashes and loose paint by a qualified chimney cleaner. This appliance is for installation only in a solid fuel burning fireplace (masonry fireplace or manufactured fireplace) with a working flue and constructed of noncombustible material.
WARNING WARNING NBST27 Unvented Gas Log Set VENTED APPLICATION INSTALLATION / SECURE APPLIANCE The fireplace and gas logs function as a system. If the fireplace is spilling into the room (check with a match or a smoke stick), reposition the damper clamp until a positive draft is obtained by opening the damper. If negative pressure in home prevents having a positive draft, contact your dealer for assistance. You must secure the gas log heater to the fireplace floor.
NBST27 Unvented Gas Log Set WARNING GAS LINE CONNECTION Use new black iron or steel pipe. Internally tinned copper or copper tubing can be used per National Fuel Code, section 2.6.3, providing gas meets hydrogen sulfide limits, and where permitted by local codes. Gas piping system must be sized to provide minimum inlet pressure (Listed on Data Plate) at the maximum flow rate (BTU/hr). Undue pressure loss will occur if the pipe is too small.
ELECTRICAL WIRING - MILLIVOLT WARNING NBST27 Unvented Gas Log Set Label all wires prior to disconnection when servicing controls. Wiring errors can cause improper and dangerous operation. Verify proper operation after servicing. The Millivolt valve is a self-powered combination gas control THAT DOES NOT REQUIRE 110VAC TO OPERATE.
ELECTRICAL WIRING - MILLIVOLT NBST27 Unvented Gas Log Set CONNECT REMOTE RECEIVER NOTICE 1. Set remote receiver. Refer to instructions included in the receiver kit. 2. Connect the two (20 1/4” female connectors to the TP/ TH and TH terminals on the control valve. Do not allow wires to touch grate of burner. NOTE: Heat reduces battery life. Protect the receiver and extend battery life by mounting receiver in wall or other location outside the fireplace.
LOG PLACEMENT The positioning of the logs is critical to the safe and clean operation of this heater. Sooting and other problems may result if the logs are not properly and firmly positioned in the appliance. Never add additional logs or embellishments such as pine cones, vermiculite or rock wool to the heater. Only use the logs and rock wool (EB-RW), and flickering embers (FBE-.1G) supplied with the unit.
LOG PLACEMENT NBST27 Unvented Gas Log Set Log 1 LOG PLACEMENT Figure 19 Place Log #1 Begin on Side A, valve on left as you face the fireplace. 1. Place log #1 on burner by aligning two (2) holes on bottom of log with two (2) pins on burner. The tallest part of the log is on the valve side of burner. Gently push log down until it comes in contact with burner surface. Figure 19 Control Valve LG650 2. Place log #2 on left grate tines by aligning the ‘V’ notches in the log with grate tines.
NBST27 Unvented Gas Log Set LOG PLACEMENT Log #5 5. Place log #5 by placing rectangular notch on bottom of log onto matching rectangular protrusion on log #2. Make sure ember or ‘burnt’ portion of log is facing center of burner. Figure 23 Figure 23 Place Log #5 LG654 Continue on Side B, valve on right as you face the fireplace. LG654 NBST log 5 Log #6 Log #1 6. Place log #6 on pilot end of burner by aligning the ‘V’ notch in bottom of log with the filler bracket surrounding the pilot.
NBST27 Unvented Gas Log Set LOG PLACEMENT 8. Place log #8 by aligning ‘V’ notch in bottom of log with the horizontal grate bar between tines as shown in Figure 17. Place the rectangular notch on bottom of log onto rectangular protrusion on middle of log #1. Figure 26 LG657 Figure 26 Place Log #8 Log #8 Log #9 LG657 NBST Log 89. Place log #9 on farthest right grate tine by aligning ‘V’ notch in bottom of log with grate tine.
NBST27 Unvented Gas Log Set FLAME APPEARANCE Flames from the pilot, front and rear burner should be visually checked as soon as the heater is installed. In addition, periodically check the flames visually during operation. Check the pilot flame The pilot flame must always be present when the heater is in operation. It should just touch the top of the thermocouple tip for natural. Refer to Figure 29 for correct pilot flame.
NBST27 Unvented Gas Log Set OPERATING INSTRUCTIONS OPERATING INSTRUCTIONS Avoid any drafts that alter burner flame patterns. Do not allow fans to blow directly into the fireplace. Do not place a blower inside the burn area of the firebox. Ceiling fans may create drafts that alter flame patterns. Sooting and improper burning will result. During manufacturing, fabricating and shipping, various components of this appliance are treated with certain oils, films or bonding agents.
NBST27 Unvented Gas Log Set OPERATING INSTRUCTIONS MILLIVOLT CONTROL LIGHTING INSTRUCTIONS 1. STOP! Read the safety information label. 2. Make sure the manual shutoff valve is fully open. 3. This gas log set is equipped with an ignition device (piezo) which automatically lights the pilot. If piezo ignitor does not light the pilot, refer to instructions for Match Lighting Instructions, Page 23. 4. Turn gas control knob clockwise to the OFF position and turn ON/OFF switch to OFF position. 5.
NBST27 Unvented Gas Log Set OPERATING INSTRUCTIONS and MAINTENANCE MATCH LIGHTING INSTRUCTIONS WARNING 1. Remove any items necessary for easy access to the pilot (for example: logs, screens, etc.). 2. Follow appropriate lighting instructions found previously. Instead of pushing and releasing the piezo button, light a match and hold the flame to the end of the pilot and ignite the pilot. 3. After control knob has been released and pilot stays lit, reinstall any items that were removed for pilot access.
WARNING NBST27 Unvented Gas Log Set TROUBLESHOOTING Turn off heater and allow to cool before cleaning. Disconnect electrical power before cleaning or servicing. Problem When ignitor button is pressed, there is not spark at ODS/pilot. Appliance produces unwanted odors. Appliance shuts off during use. NOTE: All troubleshooting items are listed in order of operation. Possible Cause 1. Ignitor electrode positioned wrong. 2. Ignitor electrode is broken. 3.
NBST27 Unvented Gas Log Set TROUBLESHOOTING Problem Possible Cause ODS/pilot lights, but flame goes out when control knob is released. Logs appear to smoke after initial operation. 1. Control knob not fully pressed in. 2. Control knob not pressed in long enough. 3. Manual shutoff valve not fully open. 4. Thermocouple connection loose at control valve. 5. Pilot flame not touching thermocouple, which allows thermocouple to cool, causing pilot flame to go out.
NBST27 Unvented Gas Log Set REPLACEMENT PARTS 1a 1h 3 1c 1b 1d 1e 1g 1f 5 2 1i 1j 8 7 6 4 WARNING Ref. 1. 1a. 1b. 1c. 1d. 1e. 1f. 1g. 1h. 1i. 1j. 2. 3. 4. 5. 6. 7. 8. 26 Description Complete Log Set Log #1 Log #2 Log #3 Log #4 Log #5 Log #6 Log #7 Log #8 Log #9 Log #10 Burner Control Valve ODS Pilot Assembly Pilot Regulator Piezo Ignitor Piezo Wire On/Off Switch Qty.
NBST27 Unvented Gas Log Set ACCESSORIES Description Flex Connector Wall Switch and Wire Wall Thermostat Kit On/Off Remote Thermostat Remote Remote Receiver Cover Ember Remote Receiver Cover Metal Log Switch with Wires Universal Andirons Rock Wool Flickering Bright Embers 81D3032 Part Number Flexcon 30 MVWS WT RCB, RCMT, TLM, WMTD RCST, RCT, TLT, WWTD RRCE RRCM ELSK UAI9 EB-RW FBE-.
NBST27 Unvented Gas Log Set 28 81D3032
NBST27 Unvented Gas Log Set 81D3032 29
Massachusetts Residents Only — Please read and follow these special requirements NOTE REGARDING VENTED PRODUCTS This product must be installed by a licensed plumber or gas fitter when installed within the Commonwealth of Massachusetts. Any residence with a direct vent product must have a CO detector installed in the residence. Installation of the fireplace or vented gas log in the State of Massachusetts requires the damper to be permanently removed or welded in the fully open position.
LIMITED LIFETIME WARRANTY POLICY Lifetime Warranty The following components are warranted for life to the original owner, subject of proof of purchase: Firebox, Combustion Chamber, Heat Exchanger, Grate, and Stainless Steel Burners. Five Year Warranty The following components are warranted for 5 years to the original owner, subject of proof of purchase: Vent Free Ceramic Fiber Logs and Aluminized Burners.
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