For example, if I pull the thermostat off my wall, the furnace should drop into a fallback mode that keeps the heat above freezing (I'm in Canada where this is a concern.)
I moved into a new house and did not set up the lawn irrigation system. Despite being disconnected from the cloud service, the system kept running its schedule, when I would have expected it turn off in order to conserve water.
A standard furnace and thermostat won’t even know if you pull the thermostat off the wall, much less have any way to handle it beyond “full blast heat 24/7”
More challenging: you expected the sprinkler setup to do the opposite. Instead of following its last-known plan (the schedule) it should stop doing anything (possibly killing the plants it’s watering)
Good off-line only mode in a reasonable plan for what to do without the Internet makes a lot of sense, but at some point, there’s a control system and you need to change it (or even just have one in the thermostat example)
I agree it's not likely (especially if the system is running as-scheduled), but it was a surprise is all. What if I didn't set up the service at all, and it dropped below 0 C? I would be in for a nasty surprise in the spring.
More interestingly (to me): did it have a local interface or was the only way to update it tied to the internet?
You have to drain them yearly.
Why does the control system have to live on someone else's server in "the cloud"?
There's no reason for smart home devices to require an internet connection to the producer's service. Companies could just as easily put compute on device, or sell some sort of "bridge" (aka a home server appliance) that runs the compute and the accessories connect to.
Fully offline, local network only.
Save the online stuff just for analytics or other value-add features, but core functionality shouldn't require a web service.
The only reason it's 100% internet connection required all the time is to sell subscriptions, aka consumer hostile behavior.
In both cases the control system is physically in your house. It sounds like the sprinkler system did work completely offline (though it's not clear if you'd actually be able to change anything without internet - that would be a problem if not), they didn't set up an account so the system was in "offline" mode and dutifully ran the sprinklers on the last known schedule.
For the thermostat the example was physically removing the control system, which is typically not connected to the furnace through any sort of internet connection, and expecting the furnace to know what to do.
I'd have expected (and strongly prefer) that it keep running with whatever the last settings were. That's almost surely going to be healthier for the lawn, ornamentals, and vegetable garden than shutting off.
I would wager that most people with automated irrigation systems prefer plant growth/protection over water conservation.
I'm not sure how you'd program a furnace to run to keep a house above freezing without any temperature feedback from the house. You could potentially run it until the area immediately surrounding the furnace itself was above freezing, but that would be nowhere near enough in some cases and way, way more than needed in other cases. You might able to use outdoor weather compensation (easier/more effective/comfortable with hydronic heat distribution than with ducted air heating) if programmed correctly, but my experience is that most are either not installed or are configured to be far too hot [because call-backs are expensive and paid by the HVAC company usually].
So it's perfectly reasonable for the furnace to turn off when it is disconnected, because disconnection would be a very strong signal for an error state instead of regular intermittent network/service issues.
Certainly, the standard smart thermostat set up is that your ecobee is connected to the Internet, but controls the furnace using good old-fashioned signal wires
The overwhelmingly most common connection between a thermostat and furnace is a contact closure when calling for heat, with no ability to differentiate between “thermostat is present but not calling for heat” and “thermostat is not present” as both present as "these T-T contacts are not closed/shorted together".
While it is controllable via the cloud, even without wifi it continues to function.
You could in theory put one next to the furnace in your machine closet but that would be dumb and expensive
Fail "safe"...not Fail "keep running"
It is extraordinarily hard to design something that can withstand that pressure and still be fit for purpose. The item needs to be able to withstand pressures in excess of ~10k psi for -10c, with the pressure rising as temp decreases.
The standard solution for people that need to winterize a building that will not be heated is to drain as much water as possible from the lines, and then fill them with a liquid with a lower freezing point.
Not running when disconnected is definitely a safe default, but I'm not sure it's automatically desired. If I found out I couldn't use my sprinkler system unless it was connected to the internet, I'd be annoyed at the unnecessary gating of such functionality.
I'd consider this a very important feature
What we need is a “in the event of X - keep doing Y”.
The furnace defaults to on to save the water pipes. The sprinkler defaults to off to conserve water as the system is potentially unmonitored and a burst pipe could cause issues.
A thermostat and controls are a necessary requirement for HVAC systems and defaulting anything to "run" if your control plane doesn't exist anymore is definitely not the safe option.
The other issue is that in almost all situations (like this one) what you think is a safe and sane default won't align with what other people think.
There should be defaults and they should be clearly defined, but I don't think it's always obvious to determine what they are.
While I agree with your overall point, this clause is irrelevant to/not supportive of it. The presence of a thermostat wasn't going to help you here either and there are vastly more furnaces with connected thermostats than disconnected to worry about.
CO detectors and alarms are needed to address this risk.
Freezing water pipes are bad, but a furnace running non-stop is going to exceed its duty cycle and pose a greater hazard.
Furnaces have multiple checks when they turned on, even on the dumbest furnaces. There are multiple safety mechanisms preventing it from getting too hot. CO leak - what thermostat will do for you here?
I had a friend in Australia who ran cattle on his farm. Failing open would waste water, but failing closed would mean dead cattle (and hundreds of thousands in losses). It depends on the application.
When it comes to safety it’s a bit more clear cut. The job of a heating system is to heat so don’t turn off heating when this can endanger people and houses.
The job of a lawn irrigation system is to irrigate. Who wants a dead lawn just because the internet or wifi are down, or to conserve water only when the system is disconnected from the internet but not from electricity?
That isn't the case, and so if the safe default is off, that definitely hampers utility, which isn't a very good selling point, heh.