Heat source under the kitchen cabinets - 2015 grand design momentum 388m

[Hogrunr]

We just purchased and are living in our 2015 grand design momentum 388m, a couple weeks ago. We battled some smells initially related to the black tank that we seen to have mostly cleared (cleared the roof vents with a snake), but now I'm trying to battle a slightly different issue. There is a heat source coming from under the kitchen cabinets that is clearly designed to vent here. However, there is a very musty, stale smell that goes along with it. I'm interested to know for sure what is the heat source and if there is anything we can do to squash the smell when it is venting this heat.

[offtohavasu]

It goes to the basement area and is the return air to the heater. You're probably getting heat from the basement area. If it's musty smelling, you may want to pull you walls down in the basement and see if there's moisture back there.

[Hogrunr]

It almost has a hint of black tank smell to it more than moisture related mustiness.

If it's the return air to the heater, why is it actively producing and blowing hot air into the kitchen?

[offtohavasu]

Are you sure it's blowing and not drafting. Hot air rises. The suggestion applies for everything you mentioned: pull the basement panels, inspect behind the panels for what would cause the smell and if anything in there is blowing air.

[Hogrunr]

Just got home and the whole kitchen/ living area has this smell. Can get on my hands and knees and feel the heat pumping into the kitchen and the smell with it. We're brand new owners, so saying "pull the basement panels" really means nothing to me.

[livinthelife]

Just got home and the whole kitchen/ living area has this smell. Can get on my hands and knees and feel the heat pumping into the kitchen and the smell with it. We're brand new owners, so saying "pull the basement panels" really means nothing to me.

The "basement panels" are the walls in the storage areas.

Open those up and see if there's been any water accumulation in the space there, that could cause off odors. You can also see if all the ducting is connected. If not, heat could be coming up anywhere.

[Hogrunr]

So this is the culprit area. I removed the cabinet panel inside. The heat isn't coming from the furnace at the front, is coming from behind. At the very back is the back side of the basement panels. I can only guess that the vacuum effect that happens inside the rv when the AC's are running, is pulling in the hot air through this area from the basement. Honestly though, the hot air doesn't bother me. It stays plenty cool in here. The smelly gasses that hilot air is mixing with is the issue.

[offtohavasu]

Was there a strong smell in the basement?

[Hogrunr]

Basement seems OK from a smell and cleanliness perspective. I'm going to try and get time later to take off the basement panel on that side to see better what I'm dealing with.

[offtohavasu]

You may want to take a look at your Air Admittance Valves (AAV) under the kitchen sink and bathroom sink.