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 firstname.lastname@example.org.
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 have arrived at a customer’s house that uses fuel oil for heat. This is a “no heat” call — the customer called first thing this morning and said that the oil furnace was not coming on, and the house was cold. When they arrived, they talked to the customer, and the customer said that he had made several tries to get the furnace to operate but with no luck.
Bob and Tim have responded to a service request where the customer is explaining that their heat pump is running all the time. The indicator light on their thermostat is lit most of the time, indicating the strip heat is on as well. The weather is cold today but has been warm some days and cold some days. It’s a very unusual heating season.
Bob and Tim are on a service call on a really cold and blustery day. The temperature is 27°F, the wind is blowing, and it’s snowing and sleeting. When the customer called, she said that their home is getting cool inside, and their heat pump is running all the time with the temperature dropping inside the house. They arrived at the front door, talked to the homeowner, and decided to look around. They went to the closet where the indoor unit for the heat pump was located and determined that the heat pump itself was not running, only the fan and strip heat.
Bob and Tim have had a big day at work — it’s 3:30 in the afternoon, and they are done for the day. They’re having coffee at a local restaurant, talking about their careers when Tim asked a question, “What is a ton of refrigeration, and why is it called a ton?”
Bob and Tim were on their way to a no heating call. When they arrived, they looked at the house and saw that it had a package unit. They talked to the housewife and she told them that the unit stopped running sometime in the middle of the night last night.
Bob and Tim were checking a customer's air conditioner and initially thought the unit must be out of refrigerant or very low on refrigerant. But after adding some refrigerant, the suction pressure did not rise at all. Bob then determined they should look for restrictions in the liquid line or the suction line.
Bob and Tim were at a customer’s house doing a seasonal checkup on a condensing gas furnace. This was routine service carried out every year on this customer’s equipment per a service agreement. But when they tried to operate the furnace, the burner would not light.
A customer was explaining what was going on with his air conditioning system. His old system had stopped working and he was told that it needed to be replaced. Money was tight and a cousin had a system removed from a rental property. So they replaced the original 3-ton package unit with a 4-ton package unit.
Bob and Tim had just arrived at a service call, the first one for the day. The complaint was that the homeowner’s air conditioning had stopped sometime in the night and the residence was hot. After their initial checks, they suspected a low charge.
Bob and Tim were on their last service call for the day. It was an apartment house with a heat pump and the weather was warm during the day and cool at night. The tenant had just moved into this apartment and was trying to get the air conditioning to operate to her satisfaction and she said it was too breezy.