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 do routine annual service on a customer’s gas furnace and humidifier. Tim asked, “What are the things that we should look for that may cause problems on a gas furnace?”
Bob and Tim were at the shop after a day of service calls. The weather was still hot, 93°F, and Bob said, “We just did a service call with a system that was overcharged and had an orifice expansion device. I would like to go into further details with you on a system with a thermostatic expansion valve (TXV) for an expansion device.”
Bob and Tim were on their way to a service call with a new customer. When they got to the job, the customer explained, "The unit was not cooling and I had a company come out for a service call. The unit seemed to work OK last week when it was a little cooler outside, but this week it has warmed up and the unit is not functioning as well."
Bob and Tim were on their way to a no cooling call; in fact, it sounded like a heating call. The customer has a bonus room on the third floor that used to be attic space. When Bob and Tim arrived, the customer told them, “The bonus room upstairs seems much too hot and the air coming out of the registers is hot to the touch.”
Bob and Tim were getting set up to clean the condenser tubes in a chiller. They were doing this job at night during overtime hours because they discovered the problem earlier that afternoon and the customer said the chiller needed to be able to operate at full capacity tomorrow for a conference.
Bob and Tim were on their way to a no cooling call at an office building with a 100-ton water-cooled chiller. As always, management was in a hurry to get the problem solved because the tenants were hot.
Bob and Tim were on their way to a no cooling call. The spring season was still cool at night and warm in the daytime. The customer told the dispatcher, “The unit started up at about 10:30 a.m. this morning and made a noise, but did not cool the house, even though it is still running.”
Bob and Tim were on their way to a no cooling call, their first of the season, when Tim asked, “Wonder why we would have a no cooling call this time of year? It is only 75°F during the day and 40° at night.”
Tim had asked Bob to go into depth about tuning an oil burner during the last service call. “You said that oil burning equipment requires more attention than any other type of residential heating equipment,” Tim said. “Can you explain why?”
Bob and Tim were on their way to an oil heat service call. It is cold and the owner has no heat. Tim read the service ticket for today and said, “The owner says that the burner won’t burn and makes a sputtering sound for a few minutes and shuts off.”