the two main to control in Refrigration?

Question 1

condensing unit on R-22

Answer 1

30 delta T

Question 2

condensing unit on R-410

Answer 2

10 to 15 delta T

Question 3

low super heat

Answer 3

overcharge

Question 4

high super heat

Answer 4

undercharge

Question 5

normal subcooling

Answer 5

10-15

Question 6

Relative himudity measured with

Answer 6

dry valve and wet valve

Question 7

75va and 24 volts

Answer 7

75va divided to 24volts 3.125 amp

Question 8

3 ton of cooling 1200

Answer 8

1200 divid to 13.33=90.02lb/mn times60minunit/hr =5400lb/hr times24 hr/day=129,600 lbs/day

Question 9

what are the three traders

Answer 9

mechanical, electrical, sheet metal dutc work

Question 10

the design charging refrigeration is

Answer 10

95 ambient temprature.

Question 11

for medium temp-refrigerator what is first to check for low charge.

Answer 11

we have to check subcooling before super heat.

Question 12

Normal super heat is?

Answer 12

8-12

Question 13

if your sub cooling is normal but high super heat what is the reason?

Answer 13

bad TXV or plug line happening.

Question 14

for high amp draw voltage what you have to check?

Answer 14

plugged up condenser

Question 15

sub cooling temp meter clamp on?

Answer 15

liquid line

Question 16

super heat temp meter clamp on?

Answer 16

suction line

Question 17

for confort what is the delta T

Answer 17

75f 40 poling point. 55f exite 75-55=20 DT

Question 18

two load condensing unit connected in

Answer 18

parallel

Question 19

what is the reason insulateing suction line?

Answer 19

to prevent from heat gaining and condensing from surrounding ambient temprature.

Question 20

defrost is always happen by

Answer 20

temperature and time

Question 21

for comercial service valve back seated? mid seated? front seated?

Answer 21

open, vacuum, close

Question 22

temperature of 95f and an inside temperature 80f with 50 humidity is ?

Answer 22

the rating establish by air conditioning

Question 23

the AHRI directory is rated under the same conditions?

Answer 23

80f db 50% humidity indoor and 95f db out door.

Question 24

what are two fixed bore metering device?

Answer 24

capillary tube and orifice (piston)

Question 25

Pumping down a refrigeration system to 5-10 pressures on the liquid line is done primarily

Answer 25

to prevent liquid refrigerant from entering the compressor during off-cycles

Question 26

restricted airflow

Answer 26

Amperage goes down

Question 27

too much air flow

Answer 27

amperage go up

Question 28

three pressures are present in the duct system are

Answer 28

total= static plus velocity

Question 29

the weakness of every force-air system.

Answer 29

Hot air rises and cold air falls