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.
Btu Buddy Notebook is a collection of more than 50 service call scenarios in book form covering both cooling season and heating season troubleshooting. For more information and to purchase the book, visit the HVACR Industry Store.
Bob and Tim were on their way to a “low heat” call at a residence when the dispatcher called them back and told them that the homeowner had called and explained that the furnace was hot, but the home was cold. The dispatcher had told the owner to shut the furnace off until Bob and Tim arrived.
Bob and Tim arrived at their fifth service call of the day. They were both wet from servicing a heat pump outdoor unit in the snow. This was a no heat call for a gas furnace. The weather was cold and there was no heat at all in the house.
Bob and Tim have gotten together after work to discuss the oil furnace service call that they were on earlier in the day. Bob had asked Tim if he would be willing to stay after work and review the call and Tim readily agreed.
Bob and Tim were on their way to a no heat call. It was an oil heat application and Tim was anxious to work on an oil system. He had not seen an actual oil heat installation, only in the school lab. Those are great, but not like the real thing at a customer’s house.
Bob and Tim have arrived at a “no cooling” call at a commercial building location. They went first to the thermostat and noticed that the indoor fan was running, but there was no cool air coming out of the air registers.
Bob and Tim were on their way to a residence outside of town where the homeowners’ complaint was excess humidity in the house. When they arrived, they met the housewife and she told them, “The plumbing fixtures often sweat, there is mold in some of the closets, and mold is beginning to form in the laundry room.”
Bob and Tim have been sent on a call to a house with no cooling. The system has just been installed and the construction crew has been having problems with startup. The system has a capillary tube metering device and Bob and Tim begin looking at what may be wrong.
Bob and Tim were on their way to a residence where the occupants said their unit runs all day long, but the space temperature rises to 82°F while the thermostat is set at 75°. The unit shuts off during the night and the temperature inside is 75° in the morning, but during the day it rises.
Bob and Tim have gone back to the job with the grounded compressor. They changed the compressor yesterday and ran the unit for a few minutes, then shut the system down, leaving the crankcase heat on so they could start it up later. They now want to determine why the compressor burned.
Bob and Tim were on their way to a no cooling call at a commercial building. When they arrived, they talked to the building manager and checked the thermostat. It was set at 72°F but the thermometer was reading 78°. Tim said, “The fan is running, so there is control voltage and the thermostat seems to be calling for cooling.”