Description Of Components; Figures And Tables - Nordyne SC038D-23A Installation Instructions Manual

DESCRIPTION OF COMPONENTS

The descriptions below are various functional components
that affect the operation and shutting down of this furnace.
Some of these components and their locations are shown
in Figures 34 and 35. If any component of the furnace
must be replaced, use only factory authorized replacement
parts specifi ed in the Replacement Parts List provided
online.
Blower Limit Switch
The Blower switch prevents furnace operation when blower
is not operational.
Condensate Drain Switch
The Condensate Drain Switch will shut down the furnace
if the condensate drain from the Collector Pan becomes
clogged.
Flame Sensor
The fl ame sensor verifi es when a fl ame has carried over
from the igniter to the opposite end burner. If no fl ame is
detected, the furnace will shut down within 4 seconds.
Flame Roll-Out Switch
The fl ame roll-out switch verifi es that the burner fl ames
are drawn into the heat exchanger tubes. If the burner
UPFLOW, DOWNFLOW & HORIZONTAL INSTALLATION CLEARANCES*
* These are the listed clearances to combustible materials.
** Allow 24 in. minimum clearance for servicing. Recommended clearance is 36 in.
The furnace is listed for installation on combustible or non-combustible fl ooring. However,
wood is the only combustible fl ooring allowed for installation. Downfl ow models must use
the appropriate subase kit when installing over a wood fl oor.
UPFLOW APPLICATION
BOTTOM

FIGURES AND TABLES

Left Side
Right Side
Vent
Back
Top
Front
HORIZONTAL APPLICATION
TOP
Table 3. Minimum Clearances to Combustible Material
fl ames are not properly drawn into the heat exchanger,
the fl ame roll-out switch will close the gas valve and
initiate the shutdown cycle.
Gas Valve
The gas valve controls the fl ow of gas to the burners.
When the gas valve is energized it automatically opens
and regulates the gas pressure in the manifold.
Inducer Assembly
The inducer assembly vents products of combustion to
the outside.
Pressure Switch
The pressure switch verifi es that the inducer is drawing
the combustion gases through the heat exchanger. If
the fl ame is not properly drawn into the heat exchanger
tube, the rollout switch or the fl ame sensor will shut the
furnace down.
Supply Air Limit Switch
The supply air limit switch prevents the air temperature
leaving the furnace from exceeding the maximum
allowable outlet air temperature.
DOWNFLOW APPLICATION
SIDE
SIDE
0 In.
0 In.
1 In.
0 In.
1 In.
4 In.**
TOP
BOTTOM
27