Have a pokémon who can use Mean Look on hand. The faster, the better. Once this rotom appears, have your pokémon trap it with Mean Look, then attempt to catch it.
This might seem a bit brutish, especially since my typical philosophy is to understand a pokémon and then meet its needs first, but rotom are unfortunately extremely quick, especially when close to sources of power. It’s better to trap it if at all possible, then attempt to communicate with it. Catching it is merely a form of security (to prevent it from escaping once Mean Look wears off), but if you’re quick or can appeal to it thoroughly, that may not entirely be necessary.
As for how to get it to come to you in the first place, this may be a bit tricky, but typically, the more appliances you have on hand, the more enticing you may make your own home. Having a lot of personal fans, for example, or computer equipment you wouldn’t mind losing—anything to give rotom a wide variety of options to possess.
Best of luck, anonymous!