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LENNOX HEARTH PRODUCTS • MERIT® SERIES B-VENT GAS FIREPLACES • MODELS MLBV-35, MLBV-40 • CARE AND OPERATION INSTRUCTIONS
Safety and Your Fireplace To prevent severe burns and injuries, install
a screen or physical barrier to prevent direct
contact with the glass.
To order a FREE Lennox
®
SAFETY GUARD
for your fireplace, see details at left.
Follow the safety instructions below
and be sure everyone in your household
understands this burn hazard:
•The surfaces on your fireplace get
EXTREMELY HOT!
•The glass on the front
of the fireplace reaches
EXTREMELY HIGH
temperatures and can
cause severe burns if touched.
•Keep children away from an operating
fireplace. Closely supervise children in
any room where a fireplace is operating
to prevent contact with glass.
•Keep clothing, furniture,
gasoline, and other
flammable liquids away
from the fireplace.
•Even after the gas is turned off, fireplace
surfaces remain extremely hot.
Be sure to attach the enclosed Safety-in-
Operation Warnings where you turn on your
replace, to help remind everyone of the
dangers associated with high temperatures
(see Page 5).
Read Important Safety Information on
Page 4.
All parts of your Lennox
Hearth Products fireplace
get EXTREMELY HOT!
TABLE OF CONTENTS
Safety and Your Fireplace........................................ 2
Important Safety Information ..................................... 4
Attaching the Safety-in-Operation Warnings ......................... 5
Appliance Installation, Service, and Maintenance Notices .................6
Appliance Operation Notices .......................................6
Warranty Information .............................................6
General Information ............................................. 7
BTU Input ....................................................7
Gas Pressure Requirements ......................................7
Orifice Sizes ..................................................7
Burn-In Period ................................................7
Operation/Care of Your Appliance ...................................8
Gas Controls / Control Compartment Access .. . . . . . . . . . . . . . . . . . . . . . . . . . 8
Appliance Controls .............................................9
Lighting the Appliance ..........................................9
ON/OFF Control ................................................9
Adjusting Flame Height ..........................................9
Controls for Optional Outside Combustion Air Kit . . . . . . . . . . . . . . . . . . . . . . . 9
Maintenance Instructions .........................................10
Removing and Installing the Glass Enclosure Panel ... . . . . . . . . . . . . . . . . . . 11
Installing Volcanic Stone, Glowing Embers (Rockwool), and Logs .........12
MLBV-35 Log Placement .......................................13
MLBV-40 Log Placement .......................................14
Burner Air Shutter Adjustments:
Flame Appearance and Sooting ...................................15
Air Shutter Adjustment Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Burner Air Shutter Adjustment Procedure ... . . . . . . . . . . . . . . . . . . . . . . . . 16
Appliance Checkout:
Millivolt Appliance Checkout .....................................16
Electronic Appliance Checkout ...................................16
Spillage Test ...................................................17
Manually-Reset Safety Limit Switch ...............................17
Ordering Replacement Parts ......................................18
Product Reference Information ....................................18
Unit Catalog Nos. / Shipping Wts. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Wiring Diagrams ...............................................18
Accessory Components ..........................................19
Lighting Instructions – Millivolt ....................................22
Lighting Instructions – Electronic .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Maintenance Schedule ...........................................26
Troubleshooting Guide – Millivolt ...................................27
Troubleshooting Guide – Electronic .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Replacement Parts List ..........................................29
Thank you for your purchase. We appreciate your business!
Please carefully read and follow all instructions in this manual.
Pay special attention to all warnings and safety information.
Following these safety, care, and operation instructions will help
ensure many years of dependable and enjoyable service from
your fireplace.
• FREE
SAFETY GUARD
OFFER •
The Lennox® SAFETY GUARD protects against
severe burns and injuries by preventing direct contact
with the front glass surface of your fireplace.
To receive your FREE SAFETY GUARD, call 1-800-786-7976
or visit www.lennox.com (Lennox Hearth Products / Owner Resources)