« previous next »

Author Question: Why should the vacuum pump isolation valve be closed before turning off the vacuum pump? What ... (Read 93 times)

bb

  • Hero Member
  • *****
  • Posts: 544
on: Jul 26, 2018
Why should the vacuum pump isolation valve be closed before turning off the vacuum pump?
 
  What will be an ideal response?

Question 2

How does an overcharge of refrigerant affect system efficiency?
 
  What will be an ideal response?


Sammyo

  • Sr. Member
  • ****
  • Posts: 329
Reply #1 on: Jul 26, 2018
Answer to Question 1

The vacuum in the system can suck the oil in the pump out of the pump and into the hoses, vacuum gauge, or even the system if left long enough.

Answer to Question 2

Overcharging will cause liquid refrigerant to back up in the condenser, increasing the operating head pressure and reducing system efficiency


Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
« previous next »
 

Did you know?

Certain chemicals, after ingestion, can be converted by the body into cyanide. Most of these chemicals have been removed from the market, but some old nail polish remover, solvents, and plastics manufacturing solutions can contain these substances.

Did you know?

Glaucoma is a leading cause of blindness. As of yet, there is no cure. Everyone is at risk, and there may be no warning signs. It is six to eight times more common in African Americans than in whites. The best and most effective way to detect glaucoma is to receive a dilated eye examination.

Did you know?

More than 4.4billion prescriptions were dispensed within the United States in 2016.

Did you know?

Dogs have been used in studies to detect various cancers in human subjects. They have been trained to sniff breath samples from humans that were collected by having them breathe into special tubes. These people included 55 lung cancer patients, 31 breast cancer patients, and 83 cancer-free patients. The dogs detected 54 of the 55 lung cancer patients as having cancer, detected 28 of the 31 breast cancer patients, and gave only three false-positive results (detecting cancer in people who didn't have it).

Did you know?

The cure for trichomoniasis is easy as long as the patient does not drink alcoholic beverages for 24 hours. Just a single dose of medication is needed to rid the body of the disease. However, without proper precautions, an individual may contract the disease repeatedly. In fact, most people develop trichomoniasis again within three months of their last treatment.

Vegetation on the mitral valve. Vegetation on the mitral valve.
A gauge reading with the needle fluctuating 3 to 9 inches Hg below normal often indicates a vacuum ... A gauge reading with the needle fluctuating 3 to 9 inches Hg below normal often indicates a vacuum ...
A demand delivery system uses a fuel-pressure regulator attached to the fuel pump assembly inside ... A demand delivery system uses a fuel-pressure regulator attached to the fuel pump assembly inside ...
The small arrows indicate the air bypassing the throttle plate in the closed throttle position. ... The small arrows indicate the air bypassing the throttle plate in the closed throttle position. ...
Using a gauge that measures vacuum in units of inches of water to test the vacuum at the dipstick ... Using a gauge that measures vacuum in units of inches of water to test the vacuum at the dipstick ...
Video: What Are Carbohydrates? Importance of Carbs & High Carb Food

For a complete list of videos, visit our video library