507712-01
Page 1 of 36
Issue 1642
Table of Contents
Unit Dimensions ............................................................2
Parts Arrangement.........................................................3
GDD80A Gas Furnace...................................................4
Shipping and Packing List .............................................4
Safety Information .........................................................4
Use of Furnace as a Construction Heater .....................5
General ..........................................................................6
Combustion, Dilution & Ventilation Air ...........................6
Setting Equipment .........................................................9
Filters ...........................................................................12
Duct System ................................................................12
Venting.........................................................................12
Gas Piping ...................................................................20
Electrical ......................................................................22
Wiring Diagrams ..........................................................24
Unit Start-Up ................................................................27
Other Unit Adjustments................................................29
Service.........................................................................31
Repair Parts List ..........................................................34
Start-Up & Performance Check List ............................35
This manual must be left with the homeowner for future reference.
INSTALLATION INSTRUCTIONS
GDD80A
Warm Air Gas Furnace
Downflow Air Discharge
This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in
manuals, be alert to the potential for personal injury or death.
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional installer (or
equivalent), service agency or the gas supplier.
WARNING
As with any mechanical equipment, personal injury can
result from contact with sharp sheet metal edges. Be
careful when you handle this equipment.
CAUTION
(P) 507712-01
*P507712-01*
Manufactured By
Comfort-Aire / Century
1900 Wellworth Ave.
Jackson, MI 49203