Mr Slim

[CitadelBlue]

We are located in northern VA just outside DC. My neighbor has a Mr Slim that heats and cools his "patio enclosure" sundeck. I noticed that the outside Mr Slim unit was running and all iced up. And I don't mean a little frost .. but alot of ice. Its in the upper 40's today and overcast. What are the possible causes for the unit to ice?

 

[JakeKohl]

We are located in northern VA just outside DC. My neighbor has a Mr Slim that heats and cools his "patio enclosure" sundeck. I noticed that the outside Mr Slim unit was running and all iced up. And I don't mean a little frost .. but alot of ice. Its in the upper 40's today and overcast. What are the possible causes for the unit to ice?

The unit may have some sort of circuit or sensor malfunction that is preventing it from entering the periodic defrost cycle (the outdoor coils are going to be very cold in heat mode - so it will need to defrost even if the outdoor temperature is well above freezing). It is also likely that he could be low on refrigerant causing a lower than normal temperature on the coils and the defrost cycle can't keep up with the amount of ice building up. Someone needs to check the charge pressures and start troubleshooting from there.