Articles and Tips

There are many ways that technicians have tried to get around actually checking the charge of air conditioners and heat pumps with superheat and subcooling! ...

On a mini-split ductless system, two copper tubes are needed to transport the refrigerant. These copper tubes are referred to as the line set and they connec...

A question that I get asked frequently is “Can I check the charge of a mini-split ductless unit with superheat and subcooling the same way I do on a conventi...

Most technicians in the HVAC field know the normal range of operation for the low-pressure side of an air conditioning system. This tends to be around 60 PSI...

In this article, we will define both superheat and total superheat, calculate total superheat, explain how to use total superheat to check the refrigerant ch...

In this article, we will define subcooling, calculate subcooling, explain how to use subcooling to check the refrigerant charge, and show where the measureme...

Regardless of the type of system or brand of thermostat, it is important to understand that there are many issues that can prevent a thermostat from operatin...

Delta T is a term that gets thrown around in the HVAC field quite a bit, but what does it really mean, what is its purpose, and does it really matter? So, wh...

The filter drier, solenoid valve, and liquid line sight have unique responsibilities in an automatic pump down refrigeration system. To use each of these com...

Short cycling means a gas furnace is running through its full sequence of operation for heat, it is providing heat in the building, and then it is shutting o...

Pilot lights can be found on furnaces, water heaters, fireplaces, ranges, ovens and other appliances. First, let’s discuss how the pilot light works before g...

Newer or faster methods do not always require expensive tools but do require a certain tool setup and step by step procedure. Some of the most labor intensiv...

The triple evacuation is meant to be a means of dehydrating refrigerant tubing in a system that has high water content before refrigerant is introduced. This...

I have been asked, “Can we braze mini-split systems instead of flaring them?”. The answer, technically, is yes. The only question is in a warranty situation,...

First of all, a liquid line restriction problem can be confirmed by measuring the following before the evaporator coil freezes: Low Vapor Saturated Temp, Hig...

The metering device is a purposeful restriction in the liquid line prior to the evaporator. The metering device is needed to lower the pressure of the liquid...

When arriving on-site to a frozen evaporator coil and suction line on an air conditioner, you should be aware that at least one of the three following proble...

If the outdoor unit has a single speed or two speed compressor running in second speed and the unit is not a Micro-channel coil, then Total Superheat or Subc...

An HVACR capacitor can be tested after turning the power off, disconnecting the wiring, and bleeding off any leftover voltage before testing. This can be don...

To determine the Target Superheat for an air conditioning system with a fixed orifice (such as a piston or capillary tube) measure the indoor WB (wet bulb) t...