ARLINGTON, VA — Combined U.S. factory shipments of 734,838 unitary air conditioners and air-source heat pumps for March are up 21% compared to the same month last year, according to Air-Conditioning and Refrigeration Institute (ARI) statistics.

Shipments for the first three months of the year total 1,681,730, which is 22% ahead of the same period last year.

Heat pump shipments included in the March figures are 133,783, up 25% compared to March 1999, with a year-to-date total of 330,634, up 18%.

Factory stocks for March increased 16,756 units from February, and climbed 122,075 units from March 99.

Distributor inventories for the month rose 76,347 units from February, and grew by 131,714 units over March 99.

March distributor shipments are up 25% from last year. Year-to-date shipments are up 17%.