# How low should a system be evacuated to?

## How low should a system be evacuated to?

400 to 500 microns
The micron gauge will determine when sufficient time has elapsed. Systems that are designed to run at 10F to 45F saturated suction temperature should be evacuated down to 400 to 500 microns. Systems designed to operate between 20F to 10F should be pulled down lower.

Is 2000 microns a good vacuum?

Why a Vacuum Pump? ASHRAE recommends evacuation to below 1000 microns for moisture removal and below 500 microns after replacing a compressor. Some equipment manufacturers call for evacuation to 400 microns to ensure that harmful water vapor is removed from the system.

### What is the required vacuum level when pulling a system evacuation?

If you cannot achieve a vacuum below 5000, it is a good indicator of a system leak, a leak in your vacuum hoses, contaminated vacuum pump oil, etc. Once you are below 5,000 microns you can be assured that dehydration is occurring and that moisture is being boiled off and removed the through evacuation process.

When should an A C system be evacuated?

Proper evacuation after initial installation or after service where the system has been opened to atmosphere is critical to proper operation of an air conditioning system. Evacuation is a two step process of degassing and dehydration.

## How evacuation is measured?

A micron is a unit of pressure starting from a perfect vacuum (no pressure) expressed in linear increments. One inch equals 25,400 microns. Evacuation is complete when a system holds 500 microns to ensure dehydration is complete. …

How many microns is a deep vacuum?

Evacuation is complete when a system holds at 500 microns. A compound gauge only indicates a vacuum is being produced. A micron gauge is the only device that accurately reads the vacuum pressure needed for deep vacuum.

### How many microns is a perfect vacuum?

In the micron vacuum scale, we start at 760,000 microns at sea-level atmospheric pressure and work down towards a perfect vacuum of 0 microns or 0″ Hg. That is why a lower number in the micron vacuum scale equals a better/deeper vacuum; a higher number equals a worse/less deep vacuum.

What is evacuating the system?

Evacuation — The removal of water vapor and air from the system.

## When does dehydration occur in an evacuation system?

Once you are below 5000 microns, you can be assured that dehydration is occurring and that moisture is being boiled off and removed through the evacuation process. Significant levels of dehydration will not occur until the vacuum level is below 1000 microns.

When does dehydration occur in a vacuum gauge?

Significant levels of dehydration are not occurring until the vacuum level is below 1,000 microns. When is comes to the vacuum gauge reading and the actual vacuum level, and an important distinction must be made. Pulling below 500 microns and being below 500 microns are two totally different things.

### How can you tell when a HVAC system is dehydrated?

An electronic vacuum gauge is the only way to determine when the dehydration process is complete. Using an electronic micron gauge like the BluVac+ Professional and its accompanying application will show you the characteristics of moisture, allowing you to identify a wet vs. a dry system easily.

When to use a dehydrated refrigeration system?

This method can be used when the ambient temperature is low as it helps to boil off any moisture and speed up the vacuum process. System has passed strength/tightness test, OFN vented off in a controlled manner.