No... I use the heater very little. So, in reality it would be an extra daily consumption.
I'm not sure if this device would allow to run 'only when needed' e.g. controlled by a thermostat or a schedule.
The consumption is 140w per hour, right?
Should be around the 100W mark, so if you run it 24/7 at $0.17 per kWh, that's 12 bucks a month.
Well, accounts can also vary based on the value of Bitcoin. Today it may not be very profitable and tomorrow it will be.
I'd like to reiterate that (especially low-power) home mining is typically not going to turn a profit. Due to residential energy prices, proportionally higher purchase price of small miners and older ASIC chips used.
Sure, you can stack those sats and sell them in the future when they're worth more, but then you could also just buy small portions of BTC every day.