One of the most common questions we get during the summer, especially during a prolonged heatwave, is “Can too much high heat overwork my AC?” The answer to this question is, “Yes and no.”
Here’s the thing… if you have your air conditioner regularly maintained each year, and you set it to a reasonable temperature, it should be able to work just as it’s intended to, without much trouble.
This means you should be calling for professional AC maintenance at least once a year… if you have a heat pump system then you’ll want professional maintenance done twice a year to keep it in good shape.
Maintenance allows our technicians to comprehensively inspect, clean, and adjust the components that need it to keep it operating as efficiently and effectively as possible, for as long as possible.
Back to the question of high heat and whether or not it can “overwork” your air conditioner… it is possible. Air conditioners do have their limits, but maybe not in the way you would think. It’s all about the temperature differential. Read on to learn what this is!
What’s the Temperature Differential?
The typical, well-maintained central air conditioner can lower the indoor temperature of your home by a maximum of 20°F below what the temperature is outside. This means if we’re experiencing a 90°F day, the coolest your air conditioner can make the inside of your living space is 70°F, and that’s not even its most efficient setting.
For energy efficiency purposes, we recommend setting your thermostat no lower than 78°F during the day, as this is the temperature most people can stay comfortable at. This setting will help your air conditioner work most efficiently, which means your energy bills will be lower.
The reason you shouldn’t go down to 70°F or lower on a 90°F day though is that your air conditioner won’t be able to actually achieve this, but will keep running and running as it tries to. It’s trying to reach an impossible level of cooling, which wastes power, leads to high energy bills, and increases the strain on the equipment which exacerbates wear and tear.
Eventually, this can cause big malfunctions with the system such as burnt-out motors or even a worn-down compressor–the compressor is the most expensive part of your system! Although the thermostat in your home can probably be lowered to 60°F, it doesn’t mean it should be.
The Reason for These Limits
Your air conditioner, depending on its size, or rather its tonnage, has a certain level of refrigerant inside of it. This is a chemical substance that resides inside the evaporator coil and makes the cooling process possible, by extracting heat out of your home.
If you have an air conditioner that’s been properly sized for your home, then it’s going to have enough refrigerant to effectively remove enough heat to lower the indoor temperature by no more than 20°F what it is outside.
Well, Can’t I Just Get a Bigger AC?
This is not the best option. Heatwaves are temporary and for the majority of the summer, it’s going to be a more reasonable temperature outside and you won’t need your air conditioner to cool any lower than 20°F below what it is outside.
So if the air conditioner is too large, or overpowered, it’s going to work inefficiently and ineffectively throughout the majority of summer.