Once the mercury rises, many people flip their thermostat from heat to cool and rely on their air conditioner to keep them comfortable all summer long. The air conditioner isn’t appreciated unless it breaks down, however, because nobody thinks about it until he or she is too hot. In fact, some people even perpetuate myths about the AC that cause damage. Here are three of them you shouldn’t believe.

1. If it Ain’t Broke Don’t Fix It

The old adage “If it ain’t broke don’t fix it” might apply to certain things, but the air conditioner is not one of them. One of the most common and harmful ac myths is that you can ignore fixing your air conditioner unless there is something seriously wrong. This is like ignoring the check engine light on your vehicle’s dashboard. Drivers who do find out eventually that what could have been a $35 oil change is now a $2,000 engine replacement.

Don’t make the same mistake with your AC. It might not have a check engine light on its thermostat but you can look for signs that there might be a minor issue. Listen to your air conditioner every time it turns on to detect any strange noises. Smell your indoor air to ensure there isn’t any unpleasant odor. Assess whether the air coming into the home is as cool as it should be. The sooner you catch a minor fix the less chance you have of it becoming a major fix.

2. Annual Maintenance Is Just the Contractor Ripping You Off

Part of ignoring the first myth is to ignore this myth. Annual maintenance on your air conditioning unit each spring is not a rip-off. Professional HVAC contractors are not out to get your money. In fact, they make a lot more money off you if you neglect to have your AC maintained once a year because it will break down eventually and have to be repair or replaced. Maintenance does not earn them more cash.

Rather, it prevents you from facing an expensive air conditioning fix down the line, and it also saves you money on your utility bills. When your AC is running at top efficiency thanks to its annual service visit, it uses less energy to keep your home cool. Think of this in an automobile sense, as well. You take your vehicle in for its recommended maintenance and your AC is a machine in need of regular service, too.

3. Turn it Off to Save More Money

Finally, this myth is a strange one, but it’s also easy to see why it gains traction. Basic common sense dictates that if it costs you money to run your air conditioner you’ll save money by turning it off. This might be true with household lights and your entertainment system, but the AC is a unique beast unto itself. When you turn the lights on and watch TV, yes, these things draw power constantly and up your electric bill. Your AC is different.

When your air conditioner shuts off after it has cooled the home to your thermostat’s set temperature, there is no energy draw. It only draws energy when it is running. If you turn off the unit completely, your house will warm up. Once your turn your air conditioner back on, it has to work twice as hard to cool everything back down. If you leave it on, it maintains your indoor air temperature, which means it runs in shorter durations and thereby uses less electricity.

Don’t be fooled by these three air conditioning myths. Fix it if it’s broke – even a minor issue – have it maintained regularly, and leave it on to prevent overworking. This will keep you cool and happy all summer long.