Suburban SF-42VHFQ Furnace 40,000 BTU SF-42F SFV-42F 2591AFeatures The SF FQ series furnaces from Suburban provide maximum heating performance in a ducted unit for increased design flexibility in large RVs. Can be easily installed in areas that might otherwise be left unused with their horizontal OR vertical installation. Specifications Dimensions: 7. 5" x 17" x 20" Weight: 29 pounds BTU h: Inputs 40,000 Voltage: 12 Ducts Required: 4 4" Required Return (in): 55" Stage: Single Discharge Type: Direct Discharge