Roof-top A/C releases torrent

[Proteus]

Hi,

I recently bought a one-owner '09 Forest River Salem SE 28 FFSB after owning a 25-foot Dutchmen class C MH for 7 years. The Salem is equipped with Dometic appliances I'm not familiar with.

During operation the A/C releases a trickle of water onto the roof and into the gutter that drips off the rear corner at the rate of a drop or 2 per second. I consider this normal and have observed it many times before in my class C.

But immediately after the A/C cycles "off" and only when it cycles off, a much larger quantity of water is suddenly released from what appears to be a hole in the bottom of the shroud (near what would be the left front corner of the roof opening). It comes in sufficient quantity and at sufficient rate that it easily overflows the gutter and flows across the slide topper and onto the ground. This flows lasts anywhere from 5 to 20+ seconds and stops as abruptly as it starts. It looks like a spigot has been opened releasing the flow.

The amount of water in that release is greatest during the hottest, most humid part of the day after the A/C has run for hours without stopping. It can flow off the slide in a stream that clears the side of the trailer by a foot or more and well wet anyone standing below. In the evening when the heat/humidity has dropped the flow may be only enough water to trickle off the topper and down the slide window, never reaching the ground.

Can someone explain what's going on here?

[dezolen]

Mine has always done the same. I don't see it as a problem

[LadyWindrider]

It has to do with air flow across the coil, and the drain pan. When it cycles off, the temp changes, the airflow changes, and the drain pan, DUMPS. It is normal. Just stay clear.

[08flagvlite]

The cooling fan inside of your unit when on is blowing air through the coils, but it also is blowing the draining condensate water the opposite direction from the drain outlet. When the ac unit shuts off, the fan stops blowing that water away from the drain, and allows gravity to take over; hence the sudden flood of water. Hope this clears up the mystery! Randy

[The_Stuff]

its all normal. the torrent of water is the cooling fins warming up and the ice buildup melting off and running down the side.

easy way to combat this is to put a slight lean to which ever corner of the trailer you want the water to run. doesn't have to be much!!

[grhodes50]

Originally Posted by 08flagvlite

The cooling fan inside of your unit when on is blowing air through the coils, but it also is blowing the draining condensate water the opposite direction from the drain outlet. When the ac unit shuts off, the fan stops blowing that water away from the drain, and allows gravity to take over; hence the sudden flood of water. Hope this clears up the mystery! Randy

Great explanation Randy.

Thanks!

[Proteus]

Thanks for the explanations! Now I understand what's happening.

[08flagvlite]

You are very welcome; glad to have helped! Randy