JOIN THE MVP PROGRAM for as little as **$9/month** Ask Us How! Read More

Skip navigation

Serving Orange County

- SINCE 1981 -

Serving Orange County

- SINCE 1981 -


Hours: Monday-Friday 7:30-5:30PM
Saturday: 8:00-1:00PM


Saddleback Plumbing Heating & Air Blog

When the Heat Rises, How Much Can You Expect From Your AC?


We’re going to be in for some serious heat during the rest of the summer in Orange County. These are the times when your home’s central air conditioning system has to get down to serious business. You need it working hard now more than ever.

This brings up a good question, one homeowners often ask: How much cooling can an AC do? Does it have a limit to watch out for?

The answer is that air conditioners do have limits, although thankfully you won’t need to push up against them often. But knowing those limits can help you enjoy energy-efficient cooling and possibly keep away a major air conditioning repair in San Juan Capistrano that interrupts the comfort in your house on a hot day.

Starting with the thermostat… 

If you’ve spent any time exploring the options of your thermostat (and we encourage this if you have Wi-Fi or smart model; they have numerous features), you’ll know there’s a lower limit to its settings. For most thermostats this is 60°F. This is one limit on your air conditioning system—you can’t set the thermostat lower than 60°F, so the AC can not be asked to lower the temperature beyond this. 

A reminder about how the thermostat works: setting the thermostat lower makes the AC run for longer to reach the target temperature. It doesn’t make it produce higher volumes of cooling or cool the home faster. A setting of 60°F is almost always a mistake, because it’s too cold for comfort for most people and will force the AC to run for far too long. We recommend never setting the thermostat lower than 68°F.

The temperature differential

The thermostat creates one limit, but your air conditioning system has a mechanical limit as well, which is called its temperature differential. This is the amount the AC can lower the indoor temperature compared to the outdoor temperature. The temperature differential for residential air conditioners is 20°; i.e. your AC can make your home a maximum of 20° cooler. 

This temperature differential is enough to handle most hot summer days. When you’re dealing with a 90°F day, the AC can make your home as cool as 70°F, which is more than cool enough. In fact, the recommended energy-saving temperature for the day when people are in the house is 78°F, which is high enough to manage days up to 98°F. Thankfully, we don’t experience many days that scorching hot.

If you push the thermostat lower than the temperature differential for your AC, it will cause the system to run and run as it tries to achieve an impossible temperature. This will run up your bills and place strain on the air conditioner that may lead to it overheating and tripping a circuit breaker in the house. The stress may even cause a repair need. As always with the AC, it’s better to raise the thermostat setting to decrease the amount of heat gain in your house and make the air conditioner’s job easier. On extremely hot days, raise the thermostat to 80°F or even above and you’ll help prevent an emergency repair call.

You can depend on our technicians if you encounter air conditioning problems this summer.

Saddleback Plumbing Heating & Air has served Orange County since 1981. Call us if you need great AC service this summer.

Comments are closed.

Let's talk about your project.