How to Adjust Air Compressor Pressure Switch

Buying a capable air compressor for your domestic needs is one thing and ensuring its smooth operation and applicability to your specific needs is another key thing to look into. The variable options of the equipment such as the pressure switch are the most pivotal consideration in order to save for yourself a lot on its operational cost and trouble as well.

Understanding the dynamics of pressure switch:

Over an air compressor, the pressure switch is of the size of your palm, resembling a rectangular shape.  It is crucial to understand the working principle of the pressure switch before we could learn how the adjustments could be precisely made.

A pressure switch or a pressure sensor is actually a device that is used for the measurement of liquid/ gas in terms of the pressure. The device shuts off once your air compressor tank is able to reach the required pressure and this phenomenon is known as the cut-off pressure.

Likewise, the same switch turns on your air compressor just as the pressure inside the tanks drop, requires more air in order to operate and this is known as the cut-on pressure.

Steps to ensure for adjusting the pressure switch of the air compressor:

  1. First thing first, begin by exposing the pressure switch by removing its cover. You will require a screwdriver in order to separate the cover from the switch. It is better to follow the cautions and instructions while working with the whole process so that there are no issues when you are opening or dealing with the setup to get the desired results.
  2. At this point, you need to connect your air compressor to the source and set it to either on or its automatic setting. This will make the compressor to work until it reaches the cut-off threshold. You need to note the pressure gauge while the equipment is in operational mode. Note down the cut-off gauge reading just as the device stops running.
  3. Now let the accumulated air out of the compressor. Then, hook-up the hose of the compressor with the unit. This should be done by pulling off over the air setting and eventually sliding down to the fitting over the nozzle. Release the hose nozzle subsequently. A blowgun will be required here for attaching that to the other end of the air hose, just as it was done with the attaching of the air hose.
  4. The blowgun’s handle needs to be pressed down in order to let go the air from the unit while taking note of the pressure gauge reading at the same time. You will notice a dip in the pressure just as the accumulated air abandons the tank. Just make sure you keep an eye on the pressure changes and the way you are working with it for a better outcome.
  5. Refer to the pressure gauge again just as the air compressor starts to work in by pushing air inside the tank. This starting threshold point will give you the cut-in pressure of the equipment. Allow time for the air compressor unit to stop.

Tuning the cut-in air pressure:

Now, you have got all the readings that you need through the above steps and this is the time to fine-tune your air compressor’s pressure switch. You will be required to have an Allen wrench or a similar tool for turning the key calibration screw towards the right side in order to amplify the cut-in pressure. On the flipside, turning the calibration screw towards left would lead to a dip in the cut-in pressure. You will find the calibration screw either just above or towards the left of the differential screw.

In many domestic air compressors, it might just be the only screw that you have. The best suggestion here is to find out about the precise information inside the operational manual of the compressor to precisely identify the placement of the adjustment screw.

In order to make the desired adjustments, you need to test by draining air out of the unit and repeating this process until you reach the accurate cut-in pressure.

Setting up the differential pressure:

For the differential pressure settings, a small (flat) screwdriver should be used for tuning the differential pressure screw. Turning the screw clockwise would amplify the differential pressure while turning it anti-clockwise would dip the same. Let the air drain out of the unit as in the first setting discussed above and make note of the pressure readings on the gauge. Continue this process until the desired differential pressure is obtained.

Once you are done with all the steps and the required adjustments discussed above for getting the desirable setting of the pressure switch, finish your activity by securely screwing back the pressure switch cover, again with the help of a screwdriver.

1 thought on “How to Adjust Air Compressor Pressure Switch”

  1. The procedure can be different depending on your air compressor pressure switch type. Some pressure switches can only be adjusted when under pressure. Don t turn any of the screws when there is zero pressure in the tank, or when your just get your new pressure switch out of the box. Always check the manual, just to be sure.


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