Fueled by a strong economy, low interest rates, and a growing replacement market, shipments of heating-cooling equipment last year totaled 14.6 million, an all-time high, and 11% higher than shipments in 1997.

The chart shows five categories of equipment. Last year’s shipments, by each category, were:

• Unitary, including heat pumps — 6,239,978, up 16%;

• Central heating, including furnaces and boilers (all fuels) — 3,438,656, up 5%;

• Room air conditioners — 4,287,000, up 12%;

• Large-tonnage centrifugal chillers — 7,558, down 14%; and

• Direct heating equipment — 660,978, down 7%. Data were provided by ARI, GAMA, AHAM.