Combustion Air; Refractories; Maintenance Guidelines - Lennox Hearth Products MAGNA-FIRE LS43ST Care And Operation Instructions Manual

IMPORTANT: The lacquer coating on the pol-
ished brass glass doors and trim pieces can
be damaged or removed causing corrosion
and/or tarnish. To help protect the solid
brass; use a non-acidic wax and avoid the
over-spray of acidic/alkali based glass clean-
ers on the brass pieces. If the solid brass
begins to turn black, all the protective coat-
ing should be removed and the metal
re-polished, either by hand or profession-
ally. Subsequently, the finish will not be as
"bright" or lustrous without the protective
coating. Solid polished brass will acquire a
patina over years of use. This is a normal
occurrence and can be polished.

COMBUSTION AIR

A proper amount of combustion air is important
for your fireplace. Fireplaces consume large
amounts of oxygen. It is important to allow an
adequate supply of air. If the fireplace is not
equipped with an outside air kit, it may not obtain
sufficient amounts of combustion air from in-
side the house or structure in which it is installed.
Therefore, the fire may draw from an outside air
source and pull air in through the chimney. This
may cause smoke spillage into the room.
Smoke spillage often occurs when a fire is first
started, until the fireplace and the chimney has
had the opportunity to "come up to tempera-
ture" and to begin to function normally. If
smoke spillage problems persist, a window
may be opened just a crack to allow the proper
flow of combustion air to the fireplace.
If your fireplace is equipped with an outside
combustion air kit, keep open at all times when
fire is burning and close when fire is out to
prevent cold air intrusion.
Combustion Air Control
On the LS43ST Series fireplace, the control
lever that operates the outside combustion air
valve is located on the lower side behind the
screen panel. Push the lever all the way up to
open the air valve and pull the lever all the way
down to close the air valve ( Figure 4 ).
Open
Closed
Figure 4
The outside air damper should be kept closed
on all fireplaces except when the fireplace is in
operation. If there is no heat present in the
firebox, the air damper should be closed at
night before retiring to prevent intrusion of
outside air into the home.
LINTEL EXTENSION
The LS43ST See-Through Factory-Built
Fireplace was designed, tested and listed with
an 20" (508 mm) high viewing area, floor to
lintel. However, varying conditions such as
altitude, climate, wood type, moisture content
of fuel, dwelling design peculiarities, average
ambient air pressure and humidity may effect
the performance of this fireplace. If an unac-
ceptable amount of smoking occurs while the
doors are open, the adjustable lintel can be
moved to correct the smoking condition.
The lintel extension can be lowered a maxi-
mum of 2" (51 mm) using a predrilled hole
located at the top of the lintel extension.
To lower the lintel extension on the LS43ST,
remove the two screws from both ends of the
lintel extension and at the center (located behind
the screen assembly). Slide the lintel extension
down and align the desired holes in the lintel
extension with the holes in the lintel frame.
Reattach using the screws previously removed.
Repeat this procedure for the lintel extension on
the opposite side of the fireplace. ( Figure 5 )
Original Position
Dimple
Lintel
Extension
Figure 5

REFRACTORIES

All fireboxes contain a furnace refractory floor.
Some models also have refractory sides and
backs. These refractories are reinforced with
steel, but can be broken by improper use. Drop-
ping logs on the bottom refractory and building
fires directly against the refractories can cause
premature burnout of these components. It may
easily be repaired or replaced at costs far below
repair and maintenance for masonry fireplaces.
NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE
Proper care and "burn-in" of the firebox will
prolong the period of enjoyment without exten-
sive maintenance. For the first few uses, build
small fires – not roaring infernos. The materials
used in the refractories contain and absorb
moisture. It is important to "cure" the refracto-
ries by building only modest fires.
Under normal usage, it is expected that hairline
cracks will appear in the refractory surface.
These hairline cracks do not affect the safe
operation of the fireplace.
Refractories should be replaced when:
1. The crack opens more than 1/4" (19 mm).
2. Pitting in the surface is extensive and pits
become deeper than 3/16" (4.76 mm).
3. Any piece of refractory larger than 2" (51 mm)
in radius and 3/16" deep becomes dislodged.
If your refractory has a crack less than 1/4"
(19 mm) in width, a simple Refractory Patch
Kit, Model RPK, can easily be used to fill the
crack and repair the refractory.
If conditions 1, 2 or 3 occur, the refractory
should be replaced. For minor defects, repair as
noted above.

MAINTENANCE GUIDELINES

Your fireplace is designed to operate trouble-
free with minimum maintenance. However, like
any fine appliance, it deserves and requires
some housekeeping attention.
Front
Frame
Your fireplace will perform better – and cer-
tainly look more attractive to family and friends
– if it is cleaned before each use. Before the first
Lintel
Frame
seasonal use in Autumn and after the last fire in
Spring, it is important to inspect the fireplace
system carefully. We recommend at least two
complete fireplace inspections a year.
Before Each Use
Lowest
Position
2" (51 mm)
1. Clean the firebox of excessive ashes. Some
owners prefer to leave a small layer to insulate
the cold refractory below the grate which helps
fire starting.
Your fireplace has a factory supplied grate
installed, it is permissible to remove the grate
for cleaning; however, the grate must be re-
attached to the fireplace before the next burn.
2. Keep the fireplace screens clean so combus-
tion air flows freely.
3. Spot check the brick-like refractory for small
cracks. Heat from the fire expands it slightly.
When it cools, it contracts.
5