The oil in a vacuum pump should be changed _____.
a. about every five minutes of pump operation
b. only when changing from one refrigerant to another
c. during or immediately after pumping down a wet system
d. about every 25 hours of pump operation
c. during or immediately after pumping down a wet system
You might also like to view...
Read the setting on this metric micrometer scale graduated in 0.01 mm.
Fill in the blank(s) with the appropriate word(s).
Which is the preferred method for tire rotation?
A) Modified "x" B) Front to rear C) Side to side D) Full "x"
Once the hantavirus has entered the lungs, the survival rate is less than _____
a. 10 percent b. 30 percent c. 40 percent d. 50 percent
The __________ mode reduces overshoot and dampens oscillations of the controlled variable.
A. proportional B. integral C. derivative