Want fewer A/C calls?
A/C systems don’t make cold air and there is no such thing as a 20 degree "rule" in HVAC. There is however a typical “delta T” (difference in temperature) that most A/C systems will make and that is an approximate 15-20 degrees cooler from the air going into the return vent compared to the air being distributed from the supply vent.
The warmer it is outside, the longer it will take to bring your home to your desired temperature. For example, if it is 100 degrees in your home and you turn on the A/C, the coolest the air coming out of the supply vent can be is 80-85 degrees and the hotter it is in your home the smaller the difference will be until your home starts to cool. So, most likely, it will be closer to 10 until the temperature starts to drop.
So, it is recommended to leave the A/C on an acceptable temperature setting and avoid turning it off while gone. If it is turned off, it may take a full day to bring your home to a comfortable temperature, even when the system works perfectly.
Make sure all filters are changed, coils are clean, the refrigerant charges are correct and not “close enough”; for that, you need good gauges and the knowledge and skill to charge by superheat and/or subcooling.
Once the A/C systems are all running well, make sure you are prepared for condensation leaks and water extractions and when the water is being cleaned up and removed it is important to use a disinfectant that will kill all germs, bacteria, and viruses. Condensation water is full of bacteria that can cause health problems.
Not all systems “just need freon”. A/C systems need more than refrigerant to work. They need airflow, as in all vents open and clean, the air filters should have no obstructions to the air entering. Keeping all doors open will help airflow and most often make a noticeable difference.
The systems need clean indoor and outdoor coils, and the fans must move enough air to properly absorb and expel heat. The refrigerant vapor line should be completely sealed in insulation as it makes a huge difference in how well the system will cool.
If the outdoor unit sits in the sun all day, it will not cool as effectively as a unit that sits in the shade.
Best tips for residents
Leave the A/C on while gone to an acceptable temperature below 80. It will help your home cool much quicker when you get home. If you turn it off, it will take much longer to cool even when it works perfectly.
If it is 100 degrees outside, it is unlikely your home will get below 74 degrees.
Change you’re A/C filters or make sure they are clean.
Do NOT wait until the end of the day to inform management your system is not working. Report it immediately. The more time the techs have during the day, the faster they can find parts if needed.
Be patient, it is very hot, and everyone wants your A/C to work as much as you do. Your techs are working hard to get it running correctly and cooling.
There are shortages across the US. for just about everything and they are doing their best to get you cool and comfortable.
Mark Cukro