Btu Buddy and Bob meet for lunch and Bob has a question about the last service call. The job involved replacing the single-wall flue pipe with double-wall pipe. “You said that we had some unfinished business about the service call yesterday, yet you said that the call was complete. What did you mean?”
In this column, Jim Johnson, director of training for Technical Training Associates, presents a specific HVACR equipment problem and invites readers to submit their diagnosis. From those who submit the correct answer by the stated deadline, there will be a prize drawing.
Bob goes on a call to a house where the residents smell fumes when the furnace is running. He examines the flue connector from the furnace to the chimney and discovers it’s rusted to the point of falling apart. With the assistance of Btu Buddy, he replaces the single-wall vent pipe with a double-wall vent.
A very common freezer repair trouble call is a frozen evaporator
coil. When you open the door to inspect the coil, look around for signs of
outside air migrating into the box.
Bob had changed a compressor and was just
about ready to charge the system when a problem arose. He pulled a vacuum down to 500 microns but noticed a rise in the vacuum gauge to 1,000 microns. There was a leak and Btu Buddy assisted him in finding it.
With this article, The NEWS is introducing a new online column called “Troubleshooting With Jim Johnson.” In this column, Jim Johnson, director of training for Technical Training Associates, will present a specific HVACR equipment problem and invite readers to submit their diagnosis.
Bob receives a call from the dispatcher to go to an office building that has a 100-ton system that is water-cooled. With the help of Btu Buddy, he finds that the water level in the cooling tower is low. They check the water fill circuit and discover a kink in the copper pipe.
When you energize a motor, you get two
outputs: a desirable one (work) and one that is not so desirable (heat).
Equipped with this knowledge, you can understand why one of the
criteria you must consider when selecting a motor for an application is the
effect of operating temperatures on that motor.
The temperature is 102° outside. The complaint is from a car dealership. The showroom temperature is 85° and the dealer is having a big sale the next day. Bob finds the a/c unit is already doing all it can. Btu Buddy shows Bob some tricks to get more out of the system.
The compressor’s discharge temperature can tell the service technician what is going on inside a refrigeration or air conditioning system. The compressor’s discharge temperature is a reflection of the hottest part of a refrigeration system, and there are limits as to how hot a discharge temperature should be. This article will explore discharge temperatures and their limits.