Forced Hot Air Furnaces : Troubleshooting and Repair

If you have a gas forced air electronic ignition system like I do forget this book. It glosses over it briefly in the first couple chapters. The troubleshooting info, pics and diagrams are taken from Lennox manuals for older forced air furnaces, mainly pilot type. The tune up info is for pilot type mainly. This book was a waste of money for my 96% Rheem furnace. I repaired my 20 yr old furnace by removing the spark ignitor and burnishing it up. I wanted to learn more about it so I bought this book...waste of time and money for my needs.

The copyright is 1999 therefore the themostats they talk about are mechanical. I haven't seen one of these in years. 80 pages are devoted to very old 80% furnaces and even that is poorly written and barely illustrated. The rest of the 341 pages focus on oil furnaces, humidifiers and other addons. They have a brief section on heat pumps but that is poorly covered. Completely a waste of money.

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.

This book didn't describe the operation of the Rheem furnace in my son's house at all. Even though I'm an electronic technician who is normally comfortable in control circuit troubleshooting, I couldn't determine why his furnace wouldn't light off. I finally ended up calling a technician out to look at it and watched how he determined the cause of the problem which turn out to be a bad ignition control module. I paid the tech $90 for the service call and then ordered the control module from Amazon. When it arrived, I installed it myself saving $200 on what the tech would have charged. I'm sorry to say that this book did nothing for me.

The material in this book is antiquated. It may have been OK 20 years ago and may be of value to some homeowners, but wouldn’t contribute much to a technician or student of the trade today. I did find it interesting.

The book states " Complete" . It is lacking in too many ways. What size ducks are necessary for how many BTU's, not there. What is the correct exhaust level readings, not discussed. What is the efficiency of flex duck verses square and round, not thereThe book is not Complete!

Good info used to help troubleshoot the system

GOOD BUY & VERY TIMELY FRO ME.