Bob got a call to go to a convention center where the air conditioning system was not working. It was a 75-ton unit with one compressor. The system was many years old, but had been functioning fine, until now. After checking out the unit, an ohm check showed 0 resistance to ground.
The poor economy has been hard on commercial businesses. In some cases, HVAC contractors still have service agreements with local malls and office buildings, but often, that work is being outsourced to national maintenance organizations. HVAC contractors have partnered with these organizations. Some sing their praises while others now turn and run.
Bob has been sent on a service call where the customer is complaining about her power bill. She thinks that the heat pump may be the problem. Her power bill is much higher than last year. She explained this to Bob and he started by asking a question, “Does the auxiliary heat light come on very often on your thermostat?”
Accurately troubleshooting and repairing refrigeration systems requires technicians to use many specialty instruments. They base many of their diagnoses on what is read from these instruments. Relying on them to be consistently accurate day in and day out is a must. If these tools are inaccurate, more than likely the diagnoses will be inaccurate.
This article is part two of a two-part series on ice flake machine troubleshooting. The last article, which appeared in the Feb. 7 NEWS, examined troubleshooting low and high water levels. This article will examine water impurities and mechanical problems.
Air conditioning coil cleaning is an important air conditioning maintenance procedure that sometimes takes some patience, and usually takes a lot of water. First, you have to make some common sense evaluations.
When the weather is warm outside, it’s imperative to make sure that your building’s mechanical cooling systems are working at maximum efficiency. Since budgets are still tight, nobody wants high energy costs or, worse, an equipment failure. The best way to avoid these bad scenarios is to perform a cooling system tuneup.
Bob and Btu Buddy were on a service call yesterday where the compressor motor was running overloaded due to internal load; the bearings were dragging or worn. Btu Buddy told Bob, “Motor overload protection and circuit protection are subjects that need to be discussed later.” They’ve gotten together today for that discussion.
While repairing refrigeration equipment, technicians sometimes come up with unique methods of solving problems. Many of these are used again and again and become known as “tricks of the trade.” When a bunch of technicians get together, they oftentimes enjoy sharing new tricks they learned or developed recently. It’s like a badge of honor.
My Feb. 7 column focused on ice flake machine troubleshooting. I will have more to say on that specific topic in my April 4 column. For this column, I want to take a look at amperage as it relates to HVACR compressors.
