[kbuck]

Or attach an ESP32 to the boiler's control board that closes a dry contact circuit...?

[mschuster91]

The problem is, if your landlord ever comes around for inspection, or the bloody thing breaks down due to your installation attempt, you can be held liable up to and including getting evicted.

[aceofspades19]

Where can you get evicted for something like that? The worst case is that they would sue your insurance for damages, or you'd have to pay them out of pocket.

[unsnap_biceps]

That was my first thought on how I would approach it as well.