9
C
LEARANCES
AND
A
CCESSIBILITY
Unobstructed front clearance of 24"
for servicing
is recom-
mended.
T O P
B1-V EN T
SIN G LE
(P LEN U M )
1"
6"
1"
3"
0"
1"
VE N T
SID ES
FR O N T
B AC K
Top clearance for horizontal configuration - 1"
I
NSTALLATION
P
OSITIONS
An upflow furnace may be installed in an upright position or
horizontal on either the left or right side panel. Do not install
this furnace on its back. For vertically installed
upflow
furnaces,
return air ductwork may be attached to the side panel(s) and/or
basepan. For
horizontally
installed
upflow
furnaces, return air
ductwork must be attached to the basepan. For
counterflow
furnaces, return ductwork must be attached to the top end of
the blower compartment.
NOTE:
Ductwork must never be attached to the back of the
furnace.
H
ORIZONTAL
I
NSTALLATION
(*MVC8 M
ODELS
O
NLY
)
Line contact to framing is permitted when installed in the hori-
zontal configuration. Line contact is defined as the portion of
the cabinet that is formed by the intersection of the top and
side. ACCESSIBILITY CLEARANCE, WHERE GREATER,
SHOULD TAKE PRECEDENCE OVER MINIMUM FIRE PRO-
TECTION CLEARANCE. A gas-fired furnace for installation in
a residential garage must be installed so that the ignition source
and burners are located not less than eighteen inches (18")
above the floor and is protected or located to prevent physical
damage by vehicles. A gas furnace must not be installed di-
rectly on carpeting, tile, or other combustible materials other
than wood flooring.
F
URNACE
S
USPENSION
If suspending the furnace from rafters or joist, use 3/8" threaded
rod and 2”x2”x3/8” angle iron as shown below. The length of
rod will depend on the application and the clearances neces-
sary.
Suspended Furnace
E
XISTING
F
URNACE
R
EMOVAL
NOTE:
When an existing furnace is removed from a venting
system serving other appliances,
the venting system may be
too large to properly vent the remaining attached appliances.
The following vent testing procedure is reproduced from the
American National Standard/National Standard of Canada
for Gas-Fired Central Furnaces ANSI Z21.47-Latest Edi-
tion, CSA-2.3-Latest Edition Section 1.23.1.
The following
steps shall be followed with each appliance connected to the
venting system placed in operation, while any other appliances
connected to the venting system are not in operation:
a.
Seal any unused openings in the venting system;
b.
Inspect the venting system for proper size and
horizontal pitch, as required by the National Fuel Gas
Code, ANSI Z223.1 or the CAN/CSA B149 Installation
Codes and these instructions. Determine that there is
no blockage or restriction, leakage, corrosion and other
deficiencies which could cause an unsafe condition;
c.
In so far as practical, close all building doors and
windows and all doors between the space in which
the appliance(s) connected to the venting system are
located and other spaces of the building. Turn on
clothes dryers and any appliance not connected to
the venting system. Turn on any exhaust fans, such
as range hoods and bathroom exhausts, so they shall
operate at maximum speed. Do not operate a summer
exhaust fan. Close fireplace dampers;
d.
Follow the lighting instructions. Place the appliance
being inspected in operation. Adjust thermostat so
appliance shall operate continuously;
e.
Test for draft hood equipped appliance spillage at the
draft hood relief opening after 5 minutes of main burner
operation. Use the flame of a match or candle;
f.
After it has been determined that each appliance
connected to the venting system properly vents when
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas
burning appliance to their previous conditions of use;
g.
If improper venting is observed during any of the above
tests, the common venting system must be corrected.
Corrections must be in accordance with the latest edition of
the National Fuel Gas Code NFPA 54/ANSI Z223.1 and/or CAN/
CSA B149 Installation Codes.
If resizing is required on any portion of the venting system, use
the appropriate table in Appendix G in the latest edition of the
National Fuel Gas Code ANSI Z223.1 and/or CAN/CSA B149
Installation Codes.
T
HERMOSTAT
L
OCATION
In an area having good air circulation, locate the thermostat
about five feet high on a vibration-free inside wall. Do not install
the thermostat where it may be influenced by any of the follow-
ing:
