Canaan Avalon Mini 3

Every other miner on this site asks you to justify the electricity. The Avalon Mini 3 doesn’t, because you were spending it anyway - it’s a baseboard heater that happens to hash at 37.5 TH/s while it warms the room. I run these at home, so this one’s written from the living room rather than the spec sheet.

The take

For me the Mini 3 resolved the tension every home miner page on this site keeps circling: the electricity is the whole cost, and mining almost never earns it back. Canaan’s answer is to stop pretending. This is a heater first - long, low, baseboard-shaped, app-controlled - and its 800 watts end up in your room like any resistive heater’s would. The difference is that a fan heater gives you warmth and nothing else, while this gives you warmth and roughly a 1-in-470 annual shot at a block. From November to March, mine carry the heating in the rooms they sit in, and the maths starts making a kind of sense it doesn’t make at any other time of year.

What the numbers actually mean

21.3 J/TH is mid-pack efficiency - a proper datacentre Antminer does better - but efficiency is the wrong lens here. Price per terahash is around £19, the cheapest on the site by a distance, and the running cost is zero if you’d have heated the room anyway. Everything hangs on that conditional: in a space you heat electrically all winter, the Mini 3 is close to a free lottery ticket at 37.5 TH/s. In a space you don’t, it’s an 800-watt appliance at UK electricity prices, and that’s roughly £4 a day. The 55 dB noise figure means conversation-level: fine in a lived-in room, wrong for a silent bedroom at full tilt, and that’s what night mode is for. Reviewers who meter one tend to see it hold that 37.5 nameplate or sit a hair above, with real-world efficiency landing nearer 19 J/TH than the quoted 21.3, but treat those as small bonuses rather than the reason to buy - the heater framing is still what makes or breaks the maths.

Living with it - noise, heat, and a closed box

This is where the Mini 3 surprised me. Run as a heater, which is how mine live, it’s genuinely quiet - a low, steady hum off the long vent that you stop noticing within a day, far closer to a baseboard heater than the industrial screech people expect from an ASIC. That quiet is a big part of why I went for it over the louder, harder-edged Avalon Q. The honest caveat is the mode: wind it all the way to full super mode and the fans have to move real air to keep the chips healthy, so it climbs toward the rated 55 dB - the sound of a gaming PC leaning on its cooler - which is still fine in a living room or a hallway but is the wrong houseguest for a silent bedroom at full tilt. Night mode goes the other way, roughly 25 TH/s and about 430 watts, down into the low-30s dB and quiet enough to sleep beside. The read that matches my own rooms: in the heater duty most people buy it for, it’s a quiet appliance; only flat out does it announce itself, and it’s still tamer than the bigger Avalon Q.

The heat is the point, not a side effect. Nearly all 800 watts end up in the room as warmth - that’s just physics, a resistive heater is 100 percent efficient and so, in that sense, is this - and the exhaust runs warm rather than scalding, so it heats the way a baseboard unit does, steadily, off a long low vent. The clever bit is heater mode: you give it a target temperature and it throttles or pauses the hashing to hold the room there, instead of dumping 800 watts flat out whether you need them or not. Swap a 1,000-watt plug-in heater for one of these in a room you’d have heated anyway and it just quietly takes over the job, only now the electricity is buying you a lottery ticket on the side.

The catch, and it’s a real one, is that the box is sealed. The firmware is Canaan’s own - no AxeOS, no undervolt tinkering, you get the modes they ship and that’s the lot. Early units were fidgety too: a few threw error codes and dropped offline in the first weeks, and flipping between heater and mining modes could hang the thing until a firmware update sorted it. Mine have been reliable since updating, but if you buy near a launch you’re partly a beta tester, and if open firmware is half the fun of this hobby for you, the whole Avalon family will frustrate you. Setup itself is quick, Bluetooth pairing to get it on Wi-Fi, but a custom solo pool goes in through the miner’s own web page rather than the app, which trips a few people up on day one.

Who should get one - and who shouldn’t

Get one if some room in your house runs on electric heat from autumn to spring - office, conservatory, garage conversion - and you’d enjoy the best home-scale solo odds going as a side effect. It’s also the obvious upgrade when a Nano 3S has charmed you and you want real hashrate: same closed-but-polished Canaan experience, six times the odds.

Don’t get one for a space that doesn’t need heating - the economics collapse entirely, and the Avalon Q conversation is the same one at double scale. And if open firmware is half the appeal of this hobby for you, the whole Avalon family will frustrate you; that’s what the Bitaxe side of the site is for.