I do wonder if it’s going to turn it into a sweatfest and less pleasant experience…?
Heat training aside, you’ll be amazed at how much heat a turbo session generates, The human body apparently produces 3 watts of heat for every watt of energy from your legs, plus whatever heat the trainer itself is churning out. My bijoux outhouse training cavern can go from a comfortable 18˚C to around 25˚C or so even with the window open. The fan means you cool slightly quicker, but it’s nowhere near as effective as riding outside. With a higher starting point, it’ll get warmer again.
I’d never measured the temperature in there until this summer, when I bought a digital thermometer / humidity meter out of curiosity and because it had felt horrifically hot in there last year. Hot enough to absolutely screw performance / up the RPE massively.
Somewhere that’s 22˚C to start with is going to get very warm indeed. Personally I’d stick with the garage. If you do want to do impromptu heat training just wear more clothes and turn off the fan. But at least you’ll the have the choice.