Forced Hot Air Furnaces: Troubleshooting, Repair & Maintenance Guide for Home Heating Systems – Perfect for Winter Comfort & Energy Efficiency

The information for the oil furnace is absolutely wonderful. The gas furnace section is for standing pilot and intermittant pilot. No mention of Direct Spark Ignition. This book illuminates descriptions and concepts that Air Conditioning and Refrigeration Technology describe. The textbook breaks furnaces broken down to their many parts. There are 3 automatic gas valves: Standing Pilot, Intermittant Pilot, and Direct Burner. There are 3 ignition systems: Intermittant Pilot (IP) or Spark to Pilot, Direct Spark Ignition (DSI), and Hot Surface Ignition (HSI). The electric furnace and heat pump information is ok. He goes into detail of the electronic air cleaner and dehumidifier that is way above what the textbook describes. This is an old book, but you still run into these furnaces. What information he provides is great. I wish he would revise his book with the newer technology on gas furnaces.