2019 Keystone Cougar

[Angus]

I keep this RV plugged in all the time. We are in south Texas so it gets very hot here, I keep the vents and windows open when I can. However the problem I am having is I just came from the RV, I turned the ac units on, I try to do this periodically. The rear unit comes one for a minute or 2 the shuts off, it blows hot air. The from unit will not come on. I have noticed when I go out there in the late evening when temperatures have come down, both units will come on when I turn them on. Does anyone kn ow why or what causes this? Thanks.

 

[M&M]

I'd wash out the AC condenser coils on roof. Probably dirty and overheating when hot outside.
Be careful not to bend the aluminum fins.