Is it Better to Turn Off the AC or Leave it On All Day?
The eternal summer debate. Discover which option consumes less energy depending on the type of equipment you have at home.
Reviewed by Carlos Martínez — Certified Technician
Approved by supervisor Rafael Casas de las Peñas Del Corral
It's the million-dollar question every summer in Madrid: *"Do I spend less if I turn the AC off when I go shopping, or is it better to leave it on at a mild temperature all day?"*
The short answer is: it depends on your technology, but in most modern cases, the rule of "always leaving it on" is a myth that will cost you more.
### The "startup spike" myth Many people believe that turning on the air conditioner draws a massive amount of energy all at once, which is why they prefer not to turn it off. This was partially true with older (ON/OFF) equipment.
However, all air conditioners sold in the last 10-15 years use Inverter technology. These compressors start up smoothly and regulate their speed gradually, eliminating large consumption spikes.
### When to TURN IT OFF (Most Recommended) - If you are leaving the house for more than 1 or 2 hours, turn it off without hesitation. Keeping an empty house cool at 24ºC for 5 hours will consume much more energy than the effort the Inverter unit will make to cool it back down when you return. - Take advantage of timers or WiFi mobile control to turn it on 20 minutes before you arrive home.
### When to LEAVE IT ON - If you are only stepping out for 15 or 30 minutes (to buy bread, walk the dog), it is better to leave it on, raising the temperature a couple of degrees (e.g., from 24ºC to 26ºC). - If you have Aerothermal Underfloor Cooling: Here the rule changes. Underfloor cooling has high "thermal inertia" (it takes a long time to cool down and warm up). In this case, it IS more efficient to leave the system running continuously at a stable temperature.
Does your AC consume too much power or take hours to cool the living room? It might be low on gas or need cleaning. Contact PowerPro Madrid. Call us or send a WhatsApp to get your equipment tuned up.
