Amprobe IR-750 Infrared-Thermometer - Manual (Page 24)

19
Measuring Grille, Register, or Diffuser Discharge Temperature
1. Press SET and then press / to select relatively high emissivity.
2. Aim the Thermometer at the discharge air grille, register, or diffuser.
3. Measure discharge temperature.
4. Release trigger to freeze the temperature reading for 8 seconds and
record this temperature.
5. Grille, register, or diffuser temperature should be equivalent to discharge
temperature at the air handler.
Checking for Blockage in Air-To-Air Evaporator or Condensers
1. Remove panels to gain access to coil return bends or hairpins.
2. Press SET and then press / to select relatively high emissivity for
copper tube.
3. Start the refrigeration system.
4. Aim the Thermometer at coil turn bends/hairpins.
5. Start recording temperature.
6. Take temperature of each return bend/hairpin.
• All evaporator return bends/hairpins should be at or slightly above
evaporator saturation temperature from the pressure/temperature chart.
• All condenser return bend/hairpins should be at or slightly less than
condenser saturation temperature.
• If a group of return bends/hairpins do not conform to expected
temperatures, that indicates a blocked or restricted distributor or
distributor tube.