Heat pump inside air handler coils frozen

Didn't expect my blog to become an HVAC repair guide, but life brings what it wants to.

My rental house full of young "adults" and I get the call the AC isn't working on a warm day.

They say the inside unit is running, air is blowing, and the fan outside on the heat pump condenser is also running normally.  But it is still warm.   Is it low freon or a blown compressor?  I hope not, that will blow months of rent money earned.

I go check it out and there is moisture on the unit and floor, it is sweaty and the insulated freon pipe to the outside is all sweaty and dripping, even icy in spots.

The air filter is sopping wet and wont come out, it seems stuck in the unit and too soggy to pull out.

I take off the cover of the air handler inside (the lower one) and instantly see the issue.   The whole coil is a humongous block of ice.   Wish i took a picture.  A little quizzing of the occupants and I get an admission that somebody turned the AC down to 60 because they were hot.

It's possible that there is low freon, but i'm betting this is user error.   I left them with the fan running and the AC unit off, telling them it will be 2 days to melt that mess.  Luckily it is only 80 today and supposed to be cooler tomorrow.

Went back after three days, luckily the weather was cool so the lack of A/C didn't get any complaints.  I replaced the filter and checked the coil.  All back to normal.  Turned on the A/C and it worked fine and cooled normally.  No harm done.  Whew.