Fix air conditioning in car

Car Air Conditioning / January 9, 2020

I call it the absence of malice problem: I only notice something is wrong because I take for granted how often everything is right. Turn the key and go; it’s what we demand of today’s cars, and it’s what we overwhelmingly get. When things do go awry, it’s always interesting to see how people cope. When your brakes go from spongy to making that funny grinding sound, you call your mechanic or drive straight to the dealership. If the engine suddenly starts cutting out, or a tire blows and you thwap to a halt by the side of the road, same thing.

But if your air conditioning starts blowing hot air, you do other things. You punch the dash; you adjust the little vents. You jam away at the settings. You turn it off and turn it on again. And again. Then you leave the car in the driveway overnight, and go out the next day and actually believe it might be OK, like it just needed a little rest so it could become air conditioning again.

My Dad didn’t believe in air conditioning, so we stuck to the plastic seat in the back of the station wagon, our small legs requiring skin grafts when we tried to move. There was a choice, of course. We could sit on a blanket instead; the temperature at sweltering levels, and we could pick between itchy wool and molten plastic. We’d fight over the windows and stick our heads out like puppies, which was fun until Mom and Dad did up their windows and my father would yell “buffeting!” and make us close them. I liked that sound, the suction of air that whumped around the interior of the car, making me think this was what outer space must sound like. Children without air conditioning develop excellent imaginations.

If your car is older and blowing hot air, you might want to give your next steps a hard think. The voyage to the root of a dead air conditioning system can be exasperating, exhausting and expensive. Your coolant has leaked out, and you can’t just top it up. It’s illegal to add a gas to your system that depletes the ozone (in Canada, usually R134A); you have to find the leak, and this is where the fun begins.

Very basically, your car’s air conditioning system is made up of three major components: the compressor, the evaporator and the condenser. There are lots of hoses, tubes, valves and sensors connecting them all. A technician has to figure out where the leak is occurring, and will pressurize the system with nitrogen to find out. This diagnostic isn’t the expensive part. Several shops told me it’s about an hour at shop rate to tell you what’s going on.

Find the leak, fix the problem, easy. Sort of. These are expensive parts and systems, and one of them – the evaporator – is usually behind the dash which requires a lot of rip-apart work. When the kids were small, I had a 10-year-old car. The air conditioning went, I foolishly let an eager young mechanic talk me into letting him fix it. I committed to Phase One believing it was Phase Done. While the 600 bucks was huge to me at the time, having the A/C working again seemed like a necessary one.

Until a week later, when I once again had vents blasting hot air. I slammed back into the garage with no good grace, demanding that he fix the fix. And that is when I learned the most valuable lesson, ever, about old cars and air conditioning.

All of the parts of that system are the same age, which means if one goes, why shouldn’t the others? Finding the leak and replacing one is zero guarantee that you can’t develop another leak in another part in a week or a month. Was I prepared to go perhaps $1, 500 dollars in to get back my arctic air? On a car that was maybe worth $2, 000? I told the kids we were now driving like in olden times.

I’ve watched mechanics explain this to a customer. I’ve witnessed the truth of the term “shooting the messenger” more times in places that specialize in auto air conditioning than just about anywhere else. My theory on expensive mechanical repairs to older vehicles is pretty simple: if a car you trust has cost you little in recent years and needs a couple grand to keep it going for another year or two, that’s cheaper than new car payments while you take some time to consider your next purchase.

My theory on air conditioning? It’s a nice-to-have, not a need-to-have for most of us. Drop the windows, find a nicer blanket and stick your head out the window.