In fact, size matters a whole LOT when it comes to wire gauge and air conditioners.
As y'all may recall, we have a home business. The bulk of it is located in the garage - husband's desk is there, the lab is there, the files and office supplies are there. The garage is not insulated. The garage is not tied into the house's central HVAC system.
It is heated and cooled using two space heaters and a portable air conditioner. They run from outlets, and one of the space heaters and the AC unit use the outlet in the laundry room so we don't blow the fuse for the garage. It also means I can't use the washer when running those. AND it means that there is a long extension cord from the laundry room to the AC unit.
Today my husband cleaned the AC air filters and vacuumed the machine. He noticed that the end of the extension cord by the AC is melted and shows scorch marks.
Not good. He decided to immediately stop using it.
Okay so far. I was to pick a new heavy duty extension cord up when I go out to get the car from the repair shop later today (remember my son's car accident? The body work is totaling $1556, but will be done around noon today).
I figured that the husband would delay using the AC until I got the new extension cord.
I was wrong.
I went out earlier than I had planned to do some chores, and came back with the cord hours before we thought I would. I found the AC running in the lab. It was hooked up to a long but really WIMPY power cord. The power cord was HOT HOT HOT. We had a real fire danger going here!
This is SO wrong. Husband wouldn't use old cord because it was scorched (and probably had been scorched for ages). But he started using an even WIMPIER extension cord? The man is NUTS. And this is a man with a PhD in Electronics!
No permanent damage done. And I brought home the most robust power cord I could get, a 10 gauge one. I don't know if the plug on it is better - it was the plug that scorched on the old one - but I hope it is so we don't have this issue again.
When I next get over to the hardware store I'll buy a new plug for the old cord, so we can replace that and have the 100 foot cord available for other things. But I'm going to watch the plug on the new cord, too. I might just end up replacing those regularly.