Mini-Split Freezing up
- Thread starter DSWalker
- Start date
Your cleaning should have covered the usual suspects.
On startup, does the complete inside coil get cold? The large pipe that goes to the outside unit should be cool to the touch.
Need to check for leaks, eliminate that. But, a common problem with mini split systems is low refrigerant in the system.
Newer systems when they came on line used 410a and the systems used higher psi to accomplish the same cooling. So, leaks are something to check. But often when they 1st charged the system they may have filled slightly lower than optimum.
Also check blower fans that could also cause this issue and make sure your systems' controller is working correctly ... turn on and off.
One additional thing the delta-T on these units is usually 25 deg +/- if you run it all the time hoping to cool like the old days it wont give it to you/ It will freeze up the system as well (trying to hit 65 deg for example when it is 100 deg outside).
Newer systems when they came on line used 410a and the systems used higher psi to accomplish the same cooling. So, leaks are something to check. But often when they 1st charged the system they may have filled slightly lower than optimum.
Also check blower fans that could also cause this issue and make sure your systems' controller is working correctly ... turn on and off.
One additional thing the delta-T on these units is usually 25 deg +/- if you run it all the time hoping to cool like the old days it wont give it to you/ It will freeze up the system as well (trying to hit 65 deg for example when it is 100 deg outside).
I generally leave it on 24/7. I had turned it down a bit as I'll be working out there regular over the next few weeks.
Cleaned it up good and bumped it back up to 77 degrees and seems to be back to normal. We have upper 90's here today and the last couple of days too. May have just been working too hard while dirty. It's probably been a couple years since I cleaned it good.
Cleaned it up good and bumped it back up to 77 degrees and seems to be back to normal. We have upper 90's here today and the last couple of days too. May have just been working too hard while dirty. It's probably been a couple years since I cleaned it good.
Freeze ups are caused by loss of refrigerate. You have a leak.
Good news, bad news. Good news it will soon not freeze up. Bad is that means you are then totally out of refrigerant.
Delta on these things is far wider than they used to be. My evaporator runs @ about 54 degrees, which is of course just above dew point so it does a terrible job of de-humidifying. Mitisubishi says that is correct. It keeps my shop @ 74 all summer with no problem. Winter has never gotten colder than 60, even when it dips single digits. New fancy coolants are not like the old R12.
Delta on these things is far wider than they used to be. My evaporator runs @ about 54 degrees, which is of course just above dew point so it does a terrible job of de-humidifying. Mitisubishi says that is correct. It keeps my shop @ 74 all summer with no problem. Winter has never gotten colder than 60, even when it dips single digits. New fancy coolants are not like the old R12.
Have you tried resetting it? I had mine stop cooling recently. Called my HVAC guy and that's all it needed. (yes it was embarassing but I'm enjoying the cool again).
It has done this before. I can't recall the time of year, but generally a good cleaning of the coils was all it took. This one was just more severe.
Certainly could be low coolant. Time will tell on that I guess.
For now, I turned the temp up a bit higher so it doesn't have to work as hard. It has worked fine this week after the cleaning and is blowing cold.
It got reset when I took everything apart to clean.
Certainly could be low coolant. Time will tell on that I guess.
For now, I turned the temp up a bit higher so it doesn't have to work as hard. It has worked fine this week after the cleaning and is blowing cold.
It got reset when I took everything apart to clean.
You should feel very lucky this week. Here, dew point is running mid- to upper-70's.
