Most air source heat pump companies are also air-conditioner manufacturers.
Air source heat pump Top Manufacturers
The list is long: Carrier, York, Danfoss, Daikin, Goodman, Lennox, Trane, Rheem, Bryant, Heil, Amana, Gibson, Rudd, Sanyo, Coleman, GE, Hayward, Ruud, Lenox, Fujitsu, Nordyne, Hayward....
Japanese companies like Mitsubishi, Fujitsy or Daikin deserve a special mention. They are leading the way to new "cold-climate" air-source heat pumps.
Most of these manufacturers are specialized in air-source heat pumps; only very few produce ground-source heat pumps.
Ground source heat pump Companies
Advanced Geothermal Technology
Bard Manufacturing Company, Inc.
Bryant Heating and Cooling Systems (Carrier Corporation)
EarthLinked Technologies, Inc.
Enertech Manufacturing, LLC
FHP Manufacturing Bosch Group
Geofinity Manufacturing Inc.
GeoSmart Energy Inc.
Johnson Controls, Inc.
Maritime Geothermal Ltd
Miami Heat Pump
Northern Heat Pump Ltd.
Spectrum Geothermal Manufacturing
WaterFurnace Int'l Inc.
International Heat Pumps Associations
Geochange Directory lists manufacturers, contractors, drilling contractors, ground loop installers, engineers, designers, distributors, architects, builders, utilities, sellers... See: GeoExchange Directory.