Ranking right up there with motor oil, coolant is one of the most important fluids in your vehicle and one that has a bunch of different responsibilities.
First and foremost, your coolant needs to (no surprise here) keep your engine temperatures under control.
Secondly, though, your coolant should be helping to support your air conditioning system – even if it isn’t specifically part of that set up.
Below we run through everything you need to know about how coolant impacts air conditioning performance and what you can do to improve the effectiveness of your AC by keeping your coolant levels consistent.
Does Coolant Affect AC Performance?
Right out of the gate you should know that your coolant is certainly going to have a major impact on your air conditioning system, even if the coolant in your radiator isn’t ever going to make its way into the AC set up.
Yes, you are reading that right – the coolant that is responsible for keeping your engine at perfect operating temperatures is not going to do the heavy lifting to keep the air inside of the cabin of your vehicle nice and cool.
But it is going to have an impact on how hard your AC works (or if it even works at all).
Low Coolant Levels Increase Temperatures
Low coolant levels in your engine bay are going to dramatically increase temperatures coming out of your engine block, and that’s going to cause overheating issues across the board.
The engine itself is going to get hotter and hotter, and that means that all of the core components of your engine are going to heat up as well.
All of that heat is going to overwhelm the coolant system that’s running low. Excess heat isn’t going to get absorbed by coolant and then exchanged through the radiator – but is instead going to heat up the coolant inside of your AC unit (and everything else, for that matter).
The end result is a whole lot more hot air being forced into the vehicle, right into the cabin. Your AC unit is going to have to work much harder to cool things down, if it’s able to keep up at all.
Low Coolant Levels Wreak Havoc with Humidity Levels
Making things worse is the fact that low coolant levels will also inevitably lead to higher humidity levels inside of your vehicle, too.
If your coolant is running low there’s not going to be enough humidity in the engine block area. The coolant won’t be able to exchange out its excess heat in the form of steam, and that means that a lot of the air getting pumped into the cabin of your vehicle is going to be bone dry.
That’s going to cause a lot of discomfort in the interior of your car. Your skin is going to dry out, your mouth is going to dry out, and you’re generally going to feel really uncomfortable.
Low Coolant Levels Restrict Airflow
Low levels of coolant will also cause problems with the airflow of your AC unit as well as the temperature of the air that inevitably makes its way from the engine block into the cabin itself.
For one thing, because the coolant is running low your engine is going to get hotter and hotter. All that heat has to go somewhere and it usually is going to find its way into the cabin – even if your AC is running on full blast.
This means that you are going to get hotter and hotter as you drive along with low levels of coolant no matter how you set or adjust your AC unit. Eventually all that hot air is simply going to overcome the climate control capabilities of your air conditioning and you’ll have to roll down the windows and hope that you can cool things down that way.
How Serious of a Problem is Low Coolant Levels?
Low coolant levels aren’t just going to wreck the effectiveness of your air conditioning system, either.
Low coolant levels can lead to extreme temperatures building up in your engine. When you combine those extreme temperatures with a lot of excessive friction from metal on metal contact with all of your engine parts you inevitably end up creating stress, pressure, and potential for catastrophic failure.
Running your vehicle with lower levels of coolant than recommended for extended amounts of time will dramatically shorten the life of your car.
All that heat is going to warp and twist even the strongest of metals and materials, throwing sensitive parts out of whack and out of sync. You might even end up seizing your engine if you run it long enough without coolant!
Combine all of that with the potential for a fire to breakout when temperatures get really hot (especially if you’re dealing with a coolant leak or an oil leak) and at the very least you are looking at seriously dangerous situations.
You could even be looking at a situation that totals your vehicle just because you weren’t staying on top of your coolant (something that only costs a few dollars to top up).
Not exactly the kind of situation you want to find yourself in, right?
How to Spot Low Coolant Levels – And Fix the Problem!
Thankfully, spotting lower coolant levels is pretty easy.
For one thing, when levels get really low the coolant sensor in the radiator system is going to trigger a light on your dashboard letting you know that you have to do something about coolant straightaway.
Secondly, a visual inspection of your engine bay every month or two will let you know when your coolant starts to run low. All you have to do then is simply top things off and you’ll be good to go.
Thirdly, it’s never a bad idea to have a mechanic doing oil changes or other regular maintenance to check your fluids and replace them as necessary.
This guarantees that hoses get checked by professionals, that the system itself is good to go, and that your coolant levels are never getting down to insufficient amounts.