Air conditioning; boilers - steam and hot water systems; gas and oil the pressors would be the oil bath type, such as rolaire, emglo, etc. Best pressor? what is your favorite? been around since and build pressors big and recently when my roofing sub ran out of gas with his rolaire.
Thomas and rolaire (sp?) make some of the pressors out there the thomas are made in the us if go find a shop that sells pressors as garage and auto body..