Guides / Air Conditioning
Delta (Δ) T Test
Procedure for Checking Air Temperature Drop ('T) across **Evaporator Coil
- 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.
- 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.
- 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.**)
- 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.**)
- 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)