Installer’s Guide
18-CD21D1-12
3
Installation Instructions
3
General Installation Instructions
4
Location and Clearances
4
Outline Drawing
5
Upflow Installation
7
Downflow Installation
7
Air For Combustion and Ventilation
8
Duct Connections
10
Return Air Filters
11
Typical Upflow Return Air Filter Installations
11
Alternate Upflow Filter Clip / Bracket Installation
13
Typical Downflow Furnace Return Air Filter Installations
13
General Venting Instructions
14
Venting Into a Masonry Chimney
15
Electrical Connections
16
Field Wiring Diagrams
17
Gas Piping
19
Sequence of Operation
19
Start Up and Adjustment
20
Preliminary Inspections
20
Combustion and Input Check
20
High Altitude Derate
21
Lighting Instructions
22
Control and Safety Switch Adjustment
23
Abnormal Conditions
23
IFC Error Flash Codes
24
Contents
▲
WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could
result in serious injury, death or property damage.
Improper servicing could result in dangerous opera-
tion, serious injury, death, or property damage.
Safety signal words are used to designate a degree
or level of seriousness associated with a particular
hazard. The signal words for safety markings are
WARNING
, and
CAUTION
.
a.
WARNING
indicates a potentially hazardous situa-
tion which, if not avoided, could result in death or
serious injury.
b.
CAUTION
indicates a potentially hazardous situa-
tion which, if not avoided, may result in minor or
moderate injury. It is also used to alert against un-
safe practices and hazards involving only property
damage.
▲
CAUTION
!
T
o prevent shortening its service life, the furnace
should not be used as a “Construction Heater” during
the finishing phases of construction until the require-
ments listed in item 9, a-g of the safety section of this
publication have been met. Condensate in the pres-
ence of chlorides and fluorides from paint, varnish,
stains, adhesives, cleaning compounds, and cement
create a corrosive condition which may cause rapid de-
terioration of the heat exchanger.
▲
WARNING
!
These furnaces are not approved or intended for instal-
lation in manufactured (mobile) housing, trailers, or
recreational vehicles.
Failure to follow this warning could result in property
damage, personal injury, or death.
▲
CAUTION
!
Do NOT install the furnace in a corrosive or contami-
nated atmosphere.
