18
M400BFC Balanced Flue Heat-Circulating Fireplace
87D1505
Installing Line for Gas Logs
MHSC fireplaces are designed to accept a 1/2” (13 mm)
gas line for installation of an approved gas appliance.
(MHSC manufactures a wide variety of gas logs for use
in MHSC fireplaces.)
Be sure to have the appliance installed in accordance
with building codes.
Gas connection may enter from either left or right side
of the fireplace.
Locate appropriate gas line in the outer casing of fire-
place and remove insulation from gas line tube. (Fig.
29)
From inside the fireplace, locate the knockout on the
firebrick -- be sure you are on the appropriate or “gas
line” side of the fireplace. Using a flat bladed screw-
driver or small chisel and hammer, carefully tap around
the knockout until it loosens and falls out.
Install 1/2” (13 mm) certified gas pipe through opening.
After gas pipe installation is complete, use insulation
that was removed from gas line tube to repack space
around the pipe. Material should be inserted from
outside of the fireplace and packed tightly to totally seal
between the pipe and tube.
Note: Gas pipe should not come in contact with
any wood structures until it has reached a point at
least 1” (25 mm) away from fireplace side.
1"
Min.
FP560a
BFC
Gas line knockout
8/00
1/2"
Hole in Outer Casing
Gas Line
Tube
Ceramic
Knockout
Supply
Line
Repack Insu-
lation
Hole in
Outer Cas-
ing
Ceramic Knockout
(both sides)
FP560a
Fig. 29
Gas line access.
Fireplace Top View
BTU input of a gas appliance installed in fireplace
should be rated less than 100,000 BTU/Hr.
Gas pipe installation is intended for connection to a
decorative gas appliance only when (1.) incorporating
an automatic shutoff device and (2.) complying with the
Standard for Decorative Gas Appliances for Installa-
tion in Vented Fireplaces (ANSI Z21.60)
or
CSA draft
requirements for Gas-Fired Log Lighters for Woodburn-
ing Fireplaces (Draft No. 4, August 1993).
Decorative gas appliance should be installed in accor-
dance with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54 (latest edition).
CAUTION: When using decorative gas
appliance, flue damper must be set in fully
open position. Glass doors on the fireplace
must also be fully opened.
WARNING: Do not operate an unvented gas
log set in this fireplace with the chimney
removed.
WARNING: When installing an unvented
gas log set, the model CABL or CABR 4”
adjustable hood must be used.
Operation
Before the first fire, the location of the upper refractory
baffle (ceiling panel) should be checked. This part floats
intentionally and may move out of place during ship-
ping or installation of the fireplace. If the baffle is out
of place, the resulting improper air flow will cause dirty
glass and improper combustion. The baffle should be
centered side-to-side between the refractory sidewalls
and be pulled forward (toward the glass doors) until it
rests on the front sheet metal ledge.
Refer to the publication “How to Enjoy Your Woodburn-
ing Fireplace” for starting and maintaining a wood fire.
Note that the M400BFC does not have a damper to
open or close. This is a tremendous efficiency increas-
ing advantage since there is no damper to potentially
leave open after a fire dies down. House air will not
escape up the chimney. Note also that the doors should
remain closed at all times except when starting or
reloading a fire.
Burn only seasoned firewood. Typically, only two or
three burning logs are needed to provide efficient sup-
plemental heat and a bright decorative fire. In general,
fresh wood should not be loaded higher than about 2/3
the height of the firebox.
