New Buck Corporation 20 Room Heater Installation And Operation Manual page 53

8. Next construct the hearth extension out of non-combustible inorganic building materials as follows:
a) The hearth extension must extend 17" in front of the rough framed opening on the ZC20.
b) The hearth extension width must be at least 37 15/16".
c) The hearth extension must be made of brick 2" thick, a listed "Hearth Extension" or "Floor Protector", or
a hearth extension made of non-combustible inorganic material with a K* factor of:
ALTERNATE FLOOR PROTECTORS MATERIALS
With the floor protector or hearth extension material specified as one layer of 2" thick brick with a K* factor of
5.0, you may use alternate materials as long as the K* factor (s) is calculated as follows:
Formula: Required thickness = (K of alternate material/K of millboard) X (thickness of millboard)
Example: An alternate inorganic non-combustible millboard with a K of .9375 would require a thickness
as follows:
Required thickness = .9375.0
K Factors of Alternate Materials:
Material
Ceroform 126
Limestone
Concrete
Sandstone
Marble
Hearth extension or floor protector thickness above four (4) inches is generally not acceptable due to cost, floor
load capacity, and look. The alternate we recommend is using Ceroform No. 126 millboard 1/8" thick minimum
and putting any type decorative brick or stone (any thickness) on top of it.
*The K* factor represents the thermal conductivity of a material and is the time rate of heat flow through a
homogeneous material under steady-state conditions, through unit area, per unit temperature gradient in the
direction perpendicular to a surface
9. The next step is the electrical installation. NOTE: An electrician must wire the ZC20 into the home wiring
system using No. 15 AWG (with ground wiring) as minimum in accordance with local wiring codes.
CAUTION: Stove is plugged into cabinet receptacle.
A. Remove brass trim.
B. Remove top panel and right side panel.
C. Now an electrician must do the wiring.
.
K = 2.5 BTU ((HR) (ft
o
x 2 inch
= 3/8 inch
K
.21
8.0
8.0
13.0
18.0
.
2 o
) ( F/in.))
Required Thickness
1/8"
3.2"
3.2"
5.2"
7.2"