In my 29 years of being in this industry, I have been asked a lot of questions related to HVAC (heating,ventilation,air conditioning). And I would say the number one is why do AC’s only last between 8 and 12 years? If you talk to Northerners, they’ll tell you they get over 20 years on their AC systems and that’s not a stretch. Consider the fact that while they are using their AC’s for 2-3 months out of the year, HVAC systems in this part of Texas are beat to death. Most HVAC systems in this part of Texas are what we call heat pump systems, which mean they can heat or cool using the refrigerant circuit and only in extreme cold will energize strip heat in the indoor air handler to supplement heating capacity. That essentially means they run almost continuously throughout the year.
Another factor to consider is the average humidity here in the Austin area. This is really the most punishing aspect of our AC systems’ responsibilities as simply removing heat does not cause anywhere near the attrition. Let’s talk some more about why only 8-12 years. I love seeing a customer with a nostalgic grin on their face talking about the system they had in their home growing up lasting over 30 years. I get a little nostalgic too, even though I’m not quite old enough to remember a Kelvinator in the kitchen, I still miss how everything was built like a tank(and about as heavy). I can testify to the absolute fact they are making things with much cheaper materials in this “corporate” world we live in these days. I remember back when I first started working in HVAC, we would roll out the copper refrigerant line sets with ease, nowadays, if you’re not extremely careful you’ll kink it in a heartbeat. The indoor evaporator coils used to have copper tubing and aluminum fins, now they are 100% aluminum.
I’ve read all the data the “suits” put out to try and convince seasoned technicians of many years why the new coil construction is so vastly superior to the old manufacturing methods, but I’m not buying it. You can’t tell me aluminum has the ability to expand and contract like copper does, is it any wonder they tend to start having leaks between about 8 and 12 years?
Typically if I find a leak in a 8 year old or older evaporator coil, I can educate most customers to see the value of starting brand new, with new warranties and a higher efficiency versus spending the money on replacing just the evaporator coil when something else major could break down at any time(usually the hottest day of the year when it is under the most stress). An evaporator coil replacement is quite expensive as well, another factor to consider before making the decision to go for the repair over the system replacement. All of the major HVAC manufacturers’ have gone to the all aluminum construction in an effort to be “competitive”. I do believe some brands are still of a higher caliber as far as their manufacturing standards, but that is another article.