3 Diagnostic Techniques HVAC Contractors Use For AC Repairs

Posted on: 26 October 2021


One of the advantages of hiring an HVAC contractor to perform work on your air conditioning system is to avoid unnecessary labor and expenses buying parts. Many do-it-yourself fixes involve throwing money at a problem and hoping for the best. On the other hand, professional technicians will diagnose your system thoroughly before installing replacement parts.

Like any other skilled tradesperson, HVAC technicians rely on a few reliable and time-tested techniques for hunting down the source of an air conditioning problem. In most cases, your repair person will use one or more of these methods to track down the issue with your air conditioning system.

1. Refrigerant Level Tests

Checking your system's refrigerant level is often the first step if a technician suspects a leak. While this might sound like a straightforward process, it's not as easy as reading a fuel gauge or checking an oil dipstick. Determining the refrigerant level in the system requires using a separate gauge set and an ability to understand the readings and interpret them.

Numerous issues can also arise from improper gauge usage. For example, the system may lose a small amount of refrigerant each time you hook up a gauge set. There's also a contamination risk with each attachment. For these reasons, even many professionals avoid hooking up level gauges unless they have a good reason to suspect an issue with your refrigerant levels.

2. Delta-T Testing

Another technique for finding problems involves testing the difference in temperature between the supply and return vents. This value is known as the delta-T, or change in temperature. A delta-T that's too high or too low can indicate a problem with your system, and this is sometimes an early indication that your refrigerant charge level is not correct.

While checking temperatures isn't as complex as checking your system's refrigerant levels, it still requires experience and knowledge to interpret this information. Technicians will use the delta-T as a single data point to help them narrow down the list of potential problems with your system.

3. Visual Inspection

Visual inspection by an experienced technician can be one of the best ways to hunt down problems. A quick check of your condenser or evaporator units will typically reveal clues to the underlying problem, allowing your contractor to more confidently determine their next steps for diagnosis or repair. These inspections can also help you avoid unnecessary tests and disassembly.

It might seem easy to go down a list of symptoms and choose the most likely solution, but reliably repairing AC problems typically requires a much more thorough diagnosis. These techniques help ensure that your technician fixes the problem on the first attempt, helping you save money and avoid repeat failures.

Contact an air conditioning repair service to learn more.