Furnace mode changes to fan(after x time) then back to furnace mode after x time? (Radio Thermostat CT30)

Looking for an app that can control how long to have the AC setting, then turn off AC to have the house run just the fan to keep air circulating. Then turn the AC back on after 10 min. Have an older AC unit that tends to freeze, and need to have a 10 min break every now and then. Any help?

Brand and model of the AC? And is it currently networked in any way, or connected to a networked thermostat or networked remote like Tado?

I am using a Radio Thermostat c30.

No clue on the make and model of the AC unit, it’s stashed in the Attic and never been up there.

Is it a C 30 or a CT 30? The air-conditioner model won’t matter as long as it’s controlled by the thermostat.

Is there an app for the thermostat and are you using it? If so, can you check what firmware level you’re on?

Oh, I should also ask if the thermostat is already on your SmartThings network or not. :sunglasses:

CT* sorry, was just going off my memory. Ya I have it connected to ST already

Excellent, that makes things simpler. :sunglasses: Hopefully someone with the same model thermostat will have some suggestions.

do you mean the coil actually freezes up?

At least two things can cause that. Low refrigerant pressure and/or restricted airflow, such as a dirty filter or dirty coil. Fixing those will save money unless you have to replace an old-style refrigerant.

I assume they were installed incorrectly, I have a drop down ceiling and when I lift a tile I feel airflow being sucked up. Keep having the service guys come back and they state I need a new AC unit. Since then I placed vents thru the ceiling tiles to help air flow. Not sure if it is going to damage it or help. I just know a new AC unit is in my near future.

Suction in the ceiling plenum (above the drop-ceiling) is normal. The cooled supply air is ducted thru the drop-ceiling to supply diffusers, cooling the occupied space. The air is allowed to return to the air handler/AC-unit because it is sucked into the ceiling through return grills. Somewhere in the ceiling is a short return duct to the AC-unit… Suction good. It’s possible there is not enough return grill area, but if you don’t hear excessive air noise then it’s probably fine.

The supply diffusers and return grills are supposed to be located to cause circulation thru the space. If they are poorly located then you might feel wider temperature variations in different areas than in an optimal arrangement. Adding return grills won’t do damage but I wouldn’t expect it to help.

If your AC-unit is really freezing then it’s wasting your electricity money and not cooling well.

I mentioned the filter because it is made to be replaced periodically, it’s cheap and easy. So it’s the first thing to try.