6
UVSRCA Vent-Free Fireboxes
20007435
A
B
B
5"
A
1/2"
C
D
T226
framing dimensions
2/04
1/2” Clearance
not Required at
This Point
Front View
Side View
A
B
C
D
UVSRC36A
39
¹⁄₄
”
44
¹⁄₄
”
21”
22”
UVSRC42A
45
¹⁄₄
”
44
¹⁄₄
”
22”
32”
T226
Fig. 4
Framing dimensions.
1"
Min.
T227
gas line install
2/04
Side Refractory
Fireplace
Outer Wrap
1/2” Gas Pipe
Refractory Cement
Noncombustible Insula-
tion
T227
Fig. 6
Gas line installation.
FP1532
Vent free
nailing flanges
10/04
Nailing
Flanges
FP1532
Fig. 5
Secure firebox.
Step 5: Gas Piping and Connection
The gas piping must be installed in accordance with
local codes or, in the absence of local codes, in accor-
dance with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54, latest edition.
The normal gas connection is 1/2” NPT, made at the left
side facing the unit. If a right side connection is desired,
the connecting pipe must be led at the rear of the fire-
place to terminate at the left hand side for connection to
the fireplace.
Piping should be tested for leaks prior to final wall
installation. Test for leaks using soap and water solution
after completing the connection. DO NOT USE OPEN
FLAME.
Step 6: Optional Procedure For Cold Climate Instal-
lations
The insulation and sealing of the enclosure around the
fireplace is very important in cold climates. If the en-
closure is insulated and sealed properly, you can avoid
future cold air problems. The time taken to install the
firebox correctly is well worthwhile. The following steps
are to stop potential cold air problems.
Insulation of the Fireplace Enclosure
When in a chase or an outside wall, the fireplace en-
closure should be insulated like any other wall of your
home. Insulation should be installed on the outside
wall(s) and the wall above the fireplace.
Insulate to Seal Under the Fireplace
Insulating under the fireplace is beneficial for installa-
tions on a concrete slab. The fireplace should be placed
on insulating board. It is important that a hard, rigid
surface be maintained, so do not use fiberglass insula-
tion for this purpose.
CAUTION:
WHEN INSTALLING A FIREPLACE IN AN
INSULATED ENCLOSURE, BE SURE TO MAINTAIN
ALL MARKED AIR SPACES.
Seal Seams
Seal the seams of the fireplace where the outer wall
meets the bottom pan and the front face. Also seal
between the fireplace and finishing materials. Use high
temperature caulk. Refer to Figure 7 for details of seal-
ing spaces between the fireplace and finishing materi-
als. Note the small amount of insulation installed across
the top of the fireplace and down the sides as a backing
for the caulk.
