We have a 2017 31SL and have a noise that I can only describe as "large drops of rain" hitting the roof. The sound that the large scattered rain drops make, just before a really hard rain storm arrives. We hear it when the heat pump shuts off. The noise continues for quit a few minutes afterwards. We think it started last year, but it was much quieter and more subdued, more like the sound of a squirrel walking around on the roof and we noticed it when the A/C would cut off.

We are using the RV this week during our spring break. The weather is cool, lows in the upper 30's/low 40's, and we are running the units in heat mode and the noise is much louder, like big rain drops. I would guess that it is related to expansion and contraction of something in the roof, but what? Is anyone else having this issue? Or is this just our unit? It's becoming quite annoying.

For additional info, we are weekender's, if that's a word, and this is the first week out this year. When we are not using the RV it is stored in our shop which is not climate-controlled.

We have this all the time when there is significant temperature change. If the roof is warm and the A/C cycles off the ducting will crackle like expansion/contraction. Same for opposite if the heat pump is running when outside temp is cold. Have always considered it normal - our A/C in the sticks and brick house would do the same.

Thanks Paul. This is our first experience with a heat pump. Our heat at home is natural gas. Our attic is well insulated so if the duct work makes any noise, we don't hear it inside.

I lived in our 2015 for 4 years and did it all winter when using the heat pumps. Duct work contracting and expanding

The duct work is made of a thin foam paneling. The heat radiates into the attic space and then the ceiling paneling expands and contracts. It drove me crazy the first year. I thought we had water leaking everywhere.

Hate to say this - but our 2013 RL is quiet as a church mouse, never makes a noise up top and we've been in it from 105 degrees to 9 degrees and windy and everything in between. Guess we got lucky.

The first time I heard it I was worried, but then it made sense that it was the duct so I slept better. It still caught me off guard sometimes, especially after forgetting about it over winter storage. You lucked out Vaughan!

Only time we have heard large rain drops was when the roof was leaking water thru the middle of the living room ceiling and we had to put a bucket on the floor! Someone at the factory drilled an extra hole thru the roof beneath the edge of the aircon unit and then didn't seal it.

I feel much better about it now. I knew there couldn't be that much water up there without it running out somewhere!