a/c problems

[henrylogan]

I have a coachman catalina sport class c rv. the a/c is icing up when I run it . have to shut it off, wait for it to deice then start it up again what causes this and how can I stop it?

[Crockett]

check seal between discharge and return air. remove grill, inspect, tape off any gaps with metal tape(aluminum, found at ace).

[Duckogram]

While you are up there, check to make sure the coil temp sensor probe is stuck in the fins of the coil. They can fall out.

[Crockett]

kudos to duckogram, I left that out. icing is generally caused by cold discharge air mixing with return air causing too much cooling on the coil. if you just switch to fan for a little while it will melt pretty quick. it happens on ducted systems more often because they have more restriction on air movement which puts more cool on the coil as well. non-ducted systems are less prone to icing and have no probe.