Thanks hubitat ...
When i go back in the winter i will disable it from going that low.
Didn't think 68 would cause freeze ups but it does when it is too cool outside.
There is a big blue sign right above thermostat that says do not set below 72. So they have no leg to stand on if they complain the thermostat was reset.
for now though
You mean pipes froze when at HVAC is at cool setpoint is at 68? Wow, that would have surprised me too.
HVAC shouldn't freeze up like that...
too much waste water is created and the coils freeze up.
its common in these systems with split air exchanger and compressor on the roof. both my units do it.. and others, thats why they put the signs on ... i didn't.
it its really humid there is lots of water generated and i dont think the little drains can keep up..
the filters become soaked and eventually freeze at the coils.
System shuts off when drain backs up..
We are right on the ocean so maybe that has something to do with it.. or the piping for the drains were put in too small.. who knows.
Have you tried an electric pump for the waste water? (what I do) That way it never has a chance to get as high as the coil
https://www.homedepot.com/p/Everbilt-120-Volt-Condensate-Pump-w-Hose-EB-PUMP-T/308593413
Interesting. Assuming you are referring to the evaporator coil freezing, I would have said that is a symptom of being undercharged. I live in Louisiana, and I can run my central unit for 12 hours without encountering that.
It isn't normal!
Second the undercharged refrigerant theory.
But low airflow from bad ductwork, a clogged filter, or fan speed set incorrectly also will cause this.
Let me guess, you have one return in the hallway someplace with a 20" grille and a 5 ton unit.
Do you have one of those awful ductopus in the attic? Those are known to cause issues.
While I agree a freeze-up at this setting may indicate other problems and also like the idea of a pump to evacuate water faster/better, I really just wanted to give @kahn-hubitat a thumbs-up/attaboy for using Hubitat to deal with this.
Two autumns ago, my wife rented our VRBO guest house for over a month in Oct/Nov to three young people who were "starving artists" working on literary pieces. She charged them a small fraction of what we normally charge because she's a nice person and as a fellow artist, was sympathetic to them. I was fine with it if she was happy (Happy wife, happy life, and all that). Anyway, they were great "kids" and we enjoyed having them around, but one of them would walk around in shorts and a tank top with the thermostat set to 80. In Maine! Temps were getting down to the teens outside!
After hearing, "Umm, I forgot" a couple of times, I just created a rule in the automation controller (pre-Hubitat for me) that turned the stat back to a reasonable temp every 1 minute. Solved that problem, and no more palm tree paradise. Wear a sweater and socks like the rest of us!
Seems like the easy fix would be to retro fit to bigger drain lines. You can't fix stupid , but you can out smart it.
On my Ecobee, I can set a maximum and minimum setpoint and an access code to access settings. Conceivably, you could make it so A/C doesn't get set lower than 72 or heat higher than 75, then set a code so they can't change those settings. Does your thermostat have something like that?
That's a great rule to reset the temperature, btw. 
It's probably cheaper to replace it with an Ecobee (assuming it is compatible) than paying for the repairs.
I like the rule to change it back on change... So if it's set to 72 and someone lowers/raises it it simply changes back
Yes i can do that to and will but you need physical access to the t6 therm to do it. I thought i was doing them a favor and 68 would be ok. But after paying for 3 service calls now 2 diff condos when we are there next will restrict them to 70.
Is there a P trap on your drain line. If not this should fix the water buildup tripping the drain pan switch.
Thats what happens .. and when the switch trips..were not there and it is service call to reset it.
Sounds like you all need to come down under.... no frozen pipes down here... Well not where I live... Our excess water lately has been coming from the sky.
Interesting legal conundrum I would expect, from the point of view of renters controlling their own environment plus the consideration for the owner of the property wanting to protect their asset.....
Not really. I mean you can build anything into a rental contract...
Download the Hubitat app
