My garage has an AC, which is never used (its so wasteful to heat and cool the room! prefer just to put on a fan)
Thinking that if i install a unit like this, i can break this in to two separate 20 amps circuits for outlets, or use the AC if i feel the need.
https://www.amazon.ca/Baomain-Universal.../dp/B08HWM7CMR/
there are no outlets, so that doesn't work! I was hoping to add additional outlets, and have enough electrical friends i could bounce the ideas off them, but didnt realize the 240 volt wiring has 2 hots and no neutral, so i cant split 1 240 volt into 2 120 volt plugs!
As a licensed electrician, I am concerned that this is over your knowledge and experience level. Best advice is to hire an electrician.
There is information missing preventing me from giving you a complete answer.
What type of AC unit?
what amperage is the AC circuit?
what voltage is the AC circuit?
is there a neutral wire?
how is the AC unit powered? (Is there a cord and receptacle, or is it hardwired to a disconnect/switch)
My guess is you have either a 20amp 220volt or 30amp 220volt AC circuit. Unfortunately, that will not work for you. Both of those types of circuits consist of 2 hot wires and a ground wire. In order to run a 120v circuit, you need a hot wire, a neutral wire, and a ground wire. Second, if it is a 30amo circuit, it is against the electrical code to put a 20amp or 15 amp receptacle on it.
That switch will not work for what you are trying to accomplish. IF you do have the correct power, just don't use the AC. If it isn't plugged in, it is not drawing any power.
I actually installed that selector in my travel trailer and it works fine. I'm just not sure if your situation requires that. What kind of outlet is your A/C hooked in to?
i looked into it more, its not going to work for me. I have 2 hot wires and a ground so no neutral to pass through to switch the 240 volt into 2 120 volt plugs.