Air Conditioner Operation

[rinaldij]

I have owned two new Keystone RV's. When doing initial checkout on both I was told not to use the A/C fan LO setting. I didn't ask then, so I'll ask now, why not?

[SC Dreamer]

They run more efficiently with as much air flow as possible.

[Triple GGG]

Prevent freeze up, especially when it's very hot.

[Bob Landry]

It has nothing to do with efficiency. If the plenum and/or ducts are not installed and taped correctly or if someone shuts off a register somewhere in the coach, an air flow restriction can occur. This is compounded by running at a slow fan speed, which also simulates an air flow problem. If everything is installed correctly and the return filters are clean, you should be able to run at slow fan speed with no issues.
The exception is... If the unit(s) are undersized for the space you are trying to cool, common in RVs, then the AC runs constantly and over an extended period will freeze up.

[rinaldij]

...

The exception is... If the unit(s) are undersized for the space you are trying to cool, common in RVs, then the AC runs constantly and over an extended period will freeze up.

Thanks. I have a Laredo 24' with a 13,500 btu a/c. Seems it should not be a problem on low fan.