506842-01
Page 1 of 42
Issue 1132
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.
As with any mechanical equipment, personal injury can
result from contact with sharp sheet metal edges. Be
careful when you handle this equipment.
CAUTION
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
(P) 506842-01
*P506842-01*
TABLE OF CONTENTS
Unit Dimensions ............................................................ 2
GUH80C
Parts Arrangement
..............
................................
3
GUH80C
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 ........................................................................ 13
Gas Piping .................................................................. 23
Electrical ..................................................................... 25
Unit Start-Up ............................................................... 29
Heating Sequence of Operation ................................. 30
Gas Pressure Adjustment ........................................... 30
High Altitude ................................................................ 31
Other Unit Adjustments ............................................... 31
Blower Motor Performance ......................................... 33
Service ........................................................................ 35
Planned Service .......................................................... 38
Integrated Control Diagnostic Codes .......................... 38
Repair Parts List ......................................................... 39
Start-Up Check List ..................................................... 40
This manual must be left with the homeowner for future reference.
INSTALLATION INSTRUCTIONS
GUH80C
Warm Air Gas Furnace
Upflow / Horizontal Left and Right Air Discharge
Manufactured By
Comfort-Aire / Century
1900 Wellworth Ave.
Jackson, MI 49203
