[TGrassey]

We have a RedLink thermostat hooked up to a 3 ton Mistubishi ducted system. We just turned it on for the first time today and the system kicked off after a short period of time with an Alert that said, "Coil Frost". I checked the insulated outdoor lines and they were roughly the same temperature as the ambient outdoor temperature. I house down the outdoor system and checked the filter in the attic unit. The filter had a little dirt on it but really not much. If it was the equivalent of a month's worth of dust from how regularly I checked the filter during the summer I'd be surprised.

Any thoughts on what I might be facing here? I though the gas was re-filled at the end of the summer but perhaps that's the issue?

 

[pecmsg]

Gas was refilled?

If they added refrigerant then there’s a leak!

 

[rider77]

The refrigerant system is a closed loop sealed circuit. Refrigerant isn’t consumed as the unit runs. It is constantly pumped around the circuit and relies on a change of state to complete its work. The refrigerant shouldn’t ever need to be “refilled”.
It sounds like you have a leak that needs to be found and fixed.

 

[TGrassey]

Thanks for the input. It sounds like a leak is the most logical answer. I've got someone coming out tomorrow to check it out.

Out of curiosity, how likely / unlikely is it that this is mechanical failure (say an issue with the A coil?) Would that produce a similar error message? The further frustrating thing about this is that the HVAC system was installed last year, and a 2 ton mini spilt was installed a month ago. Neither one was working as intended and we were in the mid 80s yesterday. Hopefully it's a simple fix for both.

 

[pecmsg]

That doesn’t sound like a good contractor!