I've placed Antminers around my apartment for heating this coming fall and winter. Steps made:
1. Undervolted and underclocked. 140 GH @ 185W.
2. Placed conveniently on shelves in most rooms except bedroom. Will run 24/7 as long as mined bitcoins are worth more than electricity. After this point will only run when I need heat.
3. Connected Ants to TP-LINK wifi routers. These are very stable, and are connected with cable to miners.
4. Fans were dissembled, then vacuumed the heat sinks, and then put fans back on.
5. Fans now run reasonably quiet at <1800 RPM. More silent than AC but would ideally be even more silent. Any tips?
Yes! same here. They are great heaters. It is Winter here in New Zealand, I have spread the old s1's around the house. It does't get too cold here, so they do a great job of keeping the house at a comfortable temperature. I call them " cash back heaters" . I have been adding s'3 in my mini data center, which is a room off the garage.