ARLINGTON, Va. — Shipments of air-source heat pumps and unitary air conditioners surged past the 7 million-unit mark for the first time in 2004, according to the Air-Conditioning and Refrigeration Institute. The year ended with 7,410,067 units shipped, eclipsing the previous record of 6,807,262 units, set in 2003.

Heat pumps jumped 16 percent ahead of 2003, ending with a record of 1,886,100 units shipped. Combined U.S. factory shipments of unitary air conditioners and air-source heat pumps for 2004 were 9 percent ahead of last year.

Factory stocks for December 2004 were down 141,537 units from November 2004, but up 1,579 units from December 2003. Distributor inventories for December 2004 were up 132,942 units for the same month the previous year, and down 37,658 units from November 2004. Distributor shipments for December 2004 were up 20 percent from December 2003, with year-to-date shipments up 5 percent.