Does hot weather heat up an electric cord?

Somewhat… But not as much as too much current!

Does hot weather heat up an electric cord

There is a question on a FB page about this hot weather making their power cord extremely hot when running their AC. But when the AC is off it isn't as hot. Is this a thing? Vanessa S.

Dear Vanessa,

Yes, hot weather will heat up a power cord somewhat from the higher ambient temperature. But not as much as passing more current through a wire than it’s rated for.

I’ll bet they’re using a light-gauge extension cord to extend their shore power cord. I’ve been getting a lot of emails from readers trying to power their RV from a skinny extension cord that’s only 14 or 16 gauge. Those are light-duty cords that are rated for 12 or 15-amperes of current.

Always use a power cord rated for the maximum amperage of the circuit breaker feeding it!

I’ve even had a few readers ask if it’s okay to use 30-to-15 and 15-to-30 amp adapters with a lightweight 16 gauge extension cord in the middle.They don’t like hauling out the heavy 10-gauge shore power cord. But that’s a recipe for disaster!

How much current can a power cord carry without overheating?

While a lightweight power cord might work with very low currents, if you plan to run an air conditioner (14 amps), plus a converter/charger (8-amps), plus a residential refrigerator (5 amps) you just have to add up 14 + 8 + 5 to get 27 amps. That’s why it’s easy to get close to tripping a 30-amp circuit breaker in the pedestal.

What happens to a 16-gauge extension cord passing 30-amps of current?

Well, I’ve done this experiment on my lab bench under controlled conditions so you don’t have to. And yes, I made a 3-minute video of it just for you…

The temperature of the extension cord I used reached over 190 degrees F in 5 minutes and I’m sure it would have melted and possibly started a fire before too much longer. Watch the video HERE.

Can you use a 12-gauge extension cord to charge your RV batteries and cool your refrigerator overnight?

In short, yes you can use a heavy-duty 12-gauge extension cord plugged into a home duplex outlet on a 20-amp circuit breaker to power much of your RV. But running an air conditioner from that limited amount of amperage is pretty tricky since turning on almost anything else in your RV can exceed the 20-amp circuit breaker rating and cause it to trip.

That circuit breaker should protect the 12-gauge extension cord from overheating and starting a fire. And that’s exactly how it’s supposed to work. However, long runs of 12-gauge extension cords can create a lot of voltage drop which causes all kinds of other problems. But that’s another article for next week.

So never use a skinny extension cord to power an RV!

Things can go wrong in a hurry with an overloaded extension cord, and a fire 🔥 in your RV is a real possibility. So never undersized an extension cord. It’s just not worth it!