Comment by llsf

1 day ago

Does anyone know if this could be used to "cap" the AC settings ? It could be useful in an airbnb place, where I want to limit the lowest (e.g. 18 degres Celsius) or hottest (e.g. 22 degres Celsius) the guest can set the AC.

Lots of digital thermostats (both relatively dumb and very smart) allow for temperature adjustments to be locked within pre-set limits. If your customer disdain drives you to want that kind of thing, then just find one and install it.

To answer your question, yes you could certainly do that and override what ever the physical thermostat was set to. You could also set max hours per day (kWh)for usage or adjust for variable rate plans. As with anything you'd need to test.

Edit: Looking through the repo and the article I see nothing blocking you. You certainly won't break anything!

If you controlled the AC temperature remotely it's a great red flag to never rent that Airbnb. Some people like it cold when they sleep.

  • I don’t think they’re proposing remotely controlling it, just so that the guest would experience being unable to change the temperature to outside the allowed range.

    Of course any guest is free to write in their review “can’t make temperature lower than 18°!” but the number of people choosing not to book for that reason in any given year is likely 0 or very close to it.

    There are a lot of people who don’t “get” thermostats and their intuitive model of ACs is like that of getting a bath to a particular temperature by turning a faucet to full hot or cold to get what they want.

    And if these people are out of the room when it reaches the actual temperature they want (and would change it), then the AC is left possibly for hours working full time, burning maximum energy and related wear and tear by trying to hopelessly achieve an unattainable temperature.

  • I understand, and I could make it clear in the description that AC is capped at 18 degres C minimum (65F), so people who like it very cold could skip my airbnb.

    Some AC can go ridiculously low (http://news.bbc.co.uk/2/hi/uk_news/england/3144803.stm). I do not want to change the temperature remotely, I just want to not have the AC used to extremely cold temperature. I am fine to advertise it to weed of people who like it very cold.

    • I should have bothered to do the conversion... when I read your post I was immediately reminded of the recent laws in Italy that capped AC in public spaces to a minimum of 25C... 18C is awfully cold for a residence!

      Most programmable thermostats in the US do have built-in limits for device protection.

      I've never met anyone who sets AC in a home to lower than 68F and that is an absolute extreme. Most central AC systems are designed for ~20 degree temperature differential so on really hot days you'd have trouble getting it that low anyway unless the system is oversized.

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    • > Some AC can go ridiculously low (http://news.bbc.co.uk/2/hi/uk_news/england/3144803.stm).

      Did you just post a link to a 23 year old news article with no sources on an http-only site as supporting evidence that your airbnb unit's AC unit can go dangerously low?

      You really think your guests will get frostbite if you don't do them the favor of limiting the AC temperature (with the unintended side-effect of saving you some money)?