There are roughly 84 well known companies making residential furnaces. Here is a list of furnace brands from A to Z.

Adams
Addison
Aire-Flo
Amana
American Standard
AquaCal
Arcoaire
Axeman-Anderson
Ariston
Armstrong

Biasi
Bryant
Buderus
Burnham

Carrier
Central Boiler
Centurion
Clare
Coleman
Columbia
Comfortmaker

Daikin
Dayton
DMO Industries
Dornback
Ducane
Dunkirk

Emerson
Evcon

Fedders
Friedrich
Frigidaire
Fulton

General Electric
Gibson
Glowcore
Goldstar
Goodman

Haier
Hallmark
Hamilton Engineering
Heat Controller
Heil
Homart

Intertherm

Janitrol

Keeprite
Kenmore
Kerr

Laars
Lennox
Luxaire

Maytag
Mitsubishi
Munchkin

Newmac

Olsen / Airco
Oneida Royal

Parker
Payne
Peerless
Pennco
Polaris

Rheem
Ruud

Samsung
Sanyo
Sears
Slant/Fin
Spartan

Tappan
Tempstar
Thermal Solutions
Thermo Pride
Trane
Trianco

Utica

Viessmann

Weatherking
Weil-McLain
Westinghouse
Whirlpool
Williamson-Thermaflo

York