Manifold sets with temperature probes can calculate and display real-time superheat and subcooling values, which can allow technicians to see real-time changes to these values. This can be very helpful when those values change rapidly during the troubleshooting process, such as on an outdoor air-cooled condenser with fan cycle controls operating in a cold ambient, or on systems where the TXV is hunting.

Some manifold gauges have a data logging function, which can be useful when troubleshooting unique problems. This can allow technicians to trend the operating pressures or a superheat/subcooling value over time to see when the problem occurs. Some also have a built-in micron gauge, which can helpful during the evacuation process. Manifold gauges with a pressure test function can track a nitrogen pressure loss over time and display the amount of pressure loss, which can make pressure testing a system a little easier.

There are also gauges that are Bluetooth enabled, which allow technicians to read the displayed value on a smartphone or tablet. This can be helpful when trying to analyze a problem while looking at two different sections of a system. Apps are also available that will help technicians troubleshoot a system problem with suggested issues based on the measured pressures and temperatures.

The drawback to a digital manifold set is that it is much more expensive than a traditional mechanical set, which could be a major consideration when purchasing. They also require batteries, which can be a pain to change or recharge when in the middle of a repair, and they can be difficult to read in direct sunlight.

Mechanical manifold gauges are still a good option for technicians, as they are less expensive. This can be helpful for new technicians entering the field and needing to purchase multiple tools at the same time. They are also easier to use, and they do not use batteries or need to be recharged. They are easier to read in direct sunlight, and they can most definitely be used to troubleshoot a system just as effectively as a digital manifold gauge.

So which is the best to carry? I think the best answer to that question is both. Many refrigeration technicians typically carry two or more sets of manifold gauges for the times when they need to work on multiple systems at the same time. Having both types of manifolds sets allows for all the advantages of each.