What is pulling a vacuum?

What is pulling a vacuum?

Pulling a vacuum on the system is simply removing matter (mostly air and nitrogen) from inside the system so that the pressure inside drops below atmospheric pressure. We use a vacuum pump specifically designed for this, and we measure the vacuum in the microns of mercury pressure scale (micron) using a vacuum gauge.

What happens if you don’t pull a vacuum?

If you do not evacuate the system to remove air and moisture, you will reduce heat transfer capability through the refrigerant because air which is 78% nitrogen is not condensable in automobile systems.

When should I pull my vacuum?

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.

Does pulling a vacuum remove oil?

Pulling a Vacuum on the system (especially for just 30 minutes) will not remove much (if any) of that oil…and only then…if it had absorbed moisture.

Does pulling a vacuum remove refrigerant?

There’s absolutely no need to use a vacuum pump to remove the refrigerant. It’s really easy to remove the refrigerant by condensing it out. If you’re a shade tree mechanic, this is what has worked for me to recover and store R134a: Get a refrigerant recovery tank with 1/4″ fittings.

Can you pull a vacuum with a leak?

Never use a vacuum to test for leaks. You will not be able to find a leak under vacuum, and you will contaminate the system with moisture and noncondensible gases. Never pull a vacuum through a Schrader valve. This practice will only increase your evacuation time due to the high restriction it will cause.

Can I leave a vacuum pump running overnight?

As the pump pulls high volumes of water vapor out of the system these vapors can condense inside the pump eventually displacing the oil and ruining the pump. Allow the vacuum pump to run overnight without supervision only after a visible inspection of the drained vacuum pump oil reveals little or no moisture.

Can you pull a vacuum on just the low side?

Yes. You can pull a vacuum from one port. The AC system is a continuous loop. There is a part known as an orifice tube which restricts the flow of refrigerant, but doesn’t stop it.

What is the purpose of pulling a vacuum on your AC system?

Pulling a vacuum is a common part of air conditioning repairs. Vacuums are used to evacuate ACs, a process by which they pull out all air and moisture from the refrigerant system prior to testing, repairs, and recharging.

How low can a vacuum pump pull?

Attach the micron gauge directly to the vacuum pump via the 1/4″ connection and verify that the pump is capable of achieving a vacuum level of 100 microns or less. A good quality pump will easily achieve levels or below 50 microns.

How long can a vacuum cleaner run continuously?

A vacuum cleaner can run continuously for 30 – 60 min each time. The vacuum cleaner has no suction power. For example, a hair cannot be sucked up.