AHRI recently released the December 2013 data on U.S. shipments of heating and cooling equipment. For December 2013, warm air furnaces are up 17.4%, driven by gas furnaces. Oil furnace shipments are down for this time period. YTD warm air furnaces are up 16.0%. Air conditioning and heat pump shipments were also up for December at 8.2% combined. YTD these units are up 9.9% driven by a 16% increase in heat pump shipments. Click here for the full report: AHRI Shipment Data.