Active in the HVACR industry since the 1950s, Bill Johnson graduated in gas fuel technology and refrigeration from the Southern Technical Institute, a branch of Georgia Tech (now known as Southern Polytechnic Institute). He taught HVAC classes at Coosa Valley Vocational & Technical Institute for four years. He moved on to become service manager for Layne Trane, Charlotte, N.C. He taught for 15 years at Central Piedmont Community College, part of this time as program director. He had his own business for five years doing installation and service work. Now retired, he is the author of Practical Heating Technology and Practical Cooling Technology, and continues as a co-author of Refrigeration & Air Conditioning Technology, seventh edition, all published by Delmar Cengage Learning. For more information, he can be reached at 704-968-0000 or thebillj1@gmail.com.
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The dispatcher called Bob and sent him to a job that really sounded like a problem. There had been a hard rain and a customer had a condensing unit that had been under water that morning due to high water from a creek behind his house. The owners were on a fixed income and wanted to get the repair at the best possible price.
Bob has been on a job at a convention center with a 100-ton water cooled condenser. The owners are anxious for Bob to get the a/c back on, but Bob said the tubes must be cleaned before the unit will run. He has called the shop and asked for a helper and a tube cleaning machine to help him get the unit running as fast as possible.
The dispatcher calls Bob with an urgent service call from the city’s convention center. A convention is going on and the air conditioner is off, and it re-starts but only runs a short time and shuts off again. The maintenance man said he had to reset the high pressure control to get it started. Btu Buddy assists in troubleshooting the system.
Bob and Btu Buddy get together for breakfast to discuss their last service call, which concerned a compressor that had liquid refrigerant flooding back to it. Bob had asked a couple of questions while they were leaving the job. Btu Buddy then proceeds to answer Bob’s questions.
This job is a three-story office building with an air handler on each floor with a refrigerant coil in each air handler. A 75-ton condensing unit serves the three 25-ton air coils. This is an old system that has still been doing a good job. The complaint is that the second floor unit is not holding the conditions that the thermostat is set for.
The day started with a call from the dispatcher who described a gas heat customer who had no heat. When Bob arrived, the first thing he noticed was that the furnace was cold. It had not been operating. At first, Bob thought that the thermostat was defective. Btu Buddy then arrived to clear up his confusion.
Bob and Btu Buddy have gotten together for coffee to discuss the previous service call and some of the questions about electric heating that came up. Btu Buddy said that they would talk about them one at a time, and probably other questions would come up.
A call has come in from a new customer that the system in a small office building is not heating properly. Bob finds the building has an electric heat furnace and, when he removes the panel, he is amazed at how many wires and terminals there are and starts to become confused. Btu Buddy arrives to assist him.
The day has been cold and damp, and Bob has been called to do a routine checkup on a heat pump in a condominium complex. Most of the units in the complex are frosted over, but the unit that he is to service has a very different frost pattern. Bob is trying to figure out what’s going on when Btu Buddy appears to help him.
Bob gets a service call where the owner says there is not enough heating at one end of an office building. With Btu Buddy's assistance, Bob checks the duct system and finds that a piece of duct liner is laying down in the duct blocking the airflow and he proceeds to correct the problem.