hvac unit 11 Flashcards
changing the instrument’s output or reading to correspond to a standard or correct reading
Calibration
used to measure temperature of vapors, liquids, and solids
temperature-measuring instruments
vapor temperatures range
0 - 150
liquid temperature range
up to 220
a popular instrument that is widely used in the hvacr industry to obtain accurate temperature readings
electronic thermocouple thermometer (flue-gas)
very convenient to carry with you and can be used effectively for taking quick field readings
digital/ pocket thermometers
three reference points for checking temperature -measuring instruments
1 - 32F (ice and water)
2 - 98.6F (body temperature)
3 - 212F (boiling point of water)
when reading the temperature of a refrigerant line…
wrap the sensor and the line with foam insulation tape
if any lead reads more than ______ from 212 degrees it is defective.
4 degrees
________ cannot be calibrated because graduations are etched on the stem
glass thermometers
a ______ is certified as to its accuracy and may be used as a standard for calibrating field instruments
laboratory-grade glass thermometer
register pressures above and below atmospheric pressure
pressure test instruments
open the gauge manifold to the atmosphere, and check both gauges to see that they read….
0 psig (it is impossible to determine a correct gauge reading if the gauge is not set at 0 at the of the test.)
1000 microns =
.54 iwc
2000 microns =
1.07 iwc
