How Do Hvac Gauges Work

How Do Manifold Gauges Work? A manifold gauge works by sending a flow of gas through the set. The yellow hose can be connected to an external source, such as a vacuum pump or refrigerant bottle. Depending on the situation, the low-pressure blue valve and high-pressure red valve would be connected appropriately.

What should HVAC gauges read?

• Blue: This color stands for gauging the suction pressure of the compressor. The reading ranges from 0 to 99.9 psi and is based on variation in atmospheric pressure.
• Red: This denotes the time and reads the pressure from the hose.

Do you add refrigerant to the high or low side?

For systems under a vacuum, once the desired vacuum level has been reached, the vacuum pump has been isolated from the system, and no leaks exist, always charge liquid refrigerant in the high side of the system until high- and low-side pressures equalize and liquid stops flowing.