Delta (Δ) T Test
Procedure for Checking Air Temperature Drop ('T) across **Evaporator Coil
1. Completely open all supply (discharge) air registers**.
2. Start the air conditioning unit and allow it to run for at least half an hour on high. The objective is to saturate the evaporator coil before running a temperature test.
3. With a standard dial-type or digital thermometer, measure the temperature of the air immediately entering the return air grill of the air conditioner unit. This is the return air temperature.
4. With a standard dial-type or digital thermometer, measure the temperature of the air immediately leaving the supply (discharge) louvres. This is the supply air temperature.
5. Subtract the supply air temperature from the return air temperature. (If it is a ducted air conditioner unit, use the closest discharge register and make sure the temperature sensing device is measuring supply air temperature only.**)
6. A properly running air conditioner unit should have a nominal temperature difference of 20°F (11.1°**C).
NOTE: Slightly lower temperature differences are possible under extremely humid conditions. (The unit may have to run longer to remove moisture.**)
7. Temperature differences greater than 22°F (-5.5°C) are possible in warm, dry weather. Restricted air- flow over the evaporator coil or low fan speed may also cause greater than 22°F (-5.5°C) temperature differences. NOTE: When using two thermometers, one for intake and one for discharge, be certain they are calibrated to each other**.
This Information comes the RVTA Level 1 A/C Textbook
Model parts lists
Full exploded parts lists (part numbers cross-checked vs the manufacturer source) for these air conditioning models:
- DOMETIC - BRISK AIR 57915321 13,500 BTU — 3104999.002 ELECTRONIC CONTROL (20 parts)
- DOMETIC - BRISK AIR 58925613 13,500 BTU — SHROUD AND MAIN COMPONENTS (96 parts)
- DOMETIC - BRISK AIR 58915306 13,500 BTU — SHROUD AND MAIN COMPONENTS (73 parts)
- DOMETIC - PENGUIN 600015001 — SHROUD & MAIN COMPONENTS (102 parts)
- COLEMAN 45203-0753 13,500 BTU — MACH 10 REPLACEMENT AC (1 parts)
- COLEMAN 45003-8794 — MACH 10 EXPLODED VIEW (38 parts)