HVAC unit 7

the size of the 1/2 inch would refer to ____ with regard to copping tubing used in plumbing and heating.. A. ID B. OD C. Length D. fitting length

A. ID

when joining sections of PVC pipe together with a union, it is always recommend to.. A. deburr the ends of the pipe and clean the pipe and fittings with primer B. deburr the ends of the pipe and avoid using primer C. leave remaining burrs in place and then clean the pipe and fittings with primer D. leave remaining burrs in place and cement the sections together without cleaning

A. deburr the ends of the pipe and clean the pipe and fittings with primer

how many perfect threads should there typically be at the end of a threaded section of steel pipe? A. 5 B. 7 C. 9 D. 11

B. 7

which two types of plastic pipe can be typically withstand temps up to 180 F? A. ABS & CPVC B. ABS & PVC C. CPVC & PE D. PE & PVC

B. ABS & PVC

the standard weight of copper tubing used most frequently in the heating and air conditioning industry is... A. K B. L C. DMV D. M

B. L

the size of 1/2 inch would refer to the _____ with regard to ACR copper tubing. A. ID B. OD C. length D. fitting length

B. OD

the most important thing to keep in mind when using a press-type mechanical pipe connecting tool is to.. A. avoid inserting the pipe sections completely into the fittings B. carefully read and follow all tool manufacturers instructions. C. ensure that the pipe and fittings are out-of-round to ensure a leak-free connection D. use a hammer to ensure that the pipe sections are secure in the fittings

B. carefully read and follow all tool manufacturers instructions.

correctly installed refrigerant piping circuits help prevent.. A. refrigerant loss and oil related compressor failure B. compressor oil return and refrigerant loss C. refrigerant loss and excess refrigerant oil in the system D. oil return and excess refrigerant in the system

B. compressor oil return and refrigerant loss

for black pipe sizes under 12 in, the nominal pipe size refers most closely to the.. A. thickness of the pipe wall B. inside the diameter of the pipe C. outside diameter of the pipe D. length of the pipe

B. inside the diameter of the pipe

which of the following statements is true regarding the flaring of copper tubing.. A. the flare nut is placed on the end of the tubing after the flare has been created B. the flare nut is placed on the end of the tubing before the flare has been created C. the flare is created by hammering the end of the soft-drawn tubing D. the flare is created by extending the tubing a distance equal to the diameter of the tubing from the flaring block

B. the flare nut is placed on the end of the tubing before the flare has been created

a common filler material used for brazing is composed of.. A. 50/50 tin-lead B. 95/5 tin-antimony C. 15% to 60% silver D. cast steel

C. 15% to 60% silver

what is the most common cause of leaking compression fittings? A. cracked compression nut B. overtightening the compression unit C. an improperly sized ring or ferrule D. pushing the tubing all the way into the fitting

C. an improperly sized ring or ferrule

the spring-type and lever-type are two kinds of tubing.. A. cutters B. reamers C. benders D. crimpers

C. benders

steel pipe is referred to as galvanized pipe when it is.. A. painted black B. coated with zinc C. coated with rust D. left bare

C. coated with rust

flux is used to A. make the filler material melt at a lower temp B. male the filler material melt at a higher temp C. help prevent oxidation D. increase the rate of oxidation formation

C. help prevent oxidation

when swaging the tubing should stick out the flaring block a distance that is approximately equal to.. A. the thickness of a nickel is 1/2in B. the thickness of the tubing wall minus 1/16in C. the outside diameter of the tubing plus 1/8in D. the radius of the tubing plus 1/4in

C. the outside diameter of the tubing plus 1/8in

all of the following statements are true regarding line sets except A. they come with special quick-connect fittings B. it is illegal to manufacture precharged line sets that contain R-22 C. they must be cut and brazed into the system D. the set consists of an uninsulated liquid line and an insulated suction line

C. they must be cut and brazed into the system

Of the following heat sources, which of them burns with the hottest flame.. A. handheld propane torch B. handheld MAPP gas torch C. air-acetylene torch D. oxyacetylene torch

D. oxyacetylene torch

the suction line on an air-conditioning or refrigeration system is insulated to A. encourage line sweating and prevent the absorption of additional heat B. encourage line sweating and allowing additional heat absorption C. prevent line sweating and prevent the absorption of additional heat D. prevent line sweating while allowing the absorption of additional heat

D. prevent line sweating while allowing the absorption of additional heat

the portion of a compression fitting that actually tightens against the tubing to create the leak-free seal is the... A. union B. coupling C. compression unit D. ring or ferrule

D. ring or ferrule

the process of expanding one end of a section of tubing so that another section of the same size tubing can be inserted into it is called.. A. flaring B. bending C. brazing D. swaging

D. swaging

why is a hacksaw not the preferred tool to use to cut copper tubing? A. it takes longer to cut tubing with a hacksaw than with a tubing center B. the hacksaw blade is not compatible with copper piping materials C. the hacksaw cannot get into places that a tubing cutter can D. the hacksaw cut produces a large amount of burrs and filings

D. the hacksaw cut produces a large amount of burrs and filings