Evans Unit Cabin Air Filtration

[turbopilot]

Best I can tell we have no cabin air filtration on the New Aire. It appears the same Evans Unit dash air handling system is the same across the Newmar Class A line.

Base on the our sneezing and dust accumulation in the cabin during our recent 5,000 mile drip in the NA it appears all the air passing by the air conditioner coils in the Evans unit is sourced from two rectangular openings just above the generator. When you select the "Recirc" mode two foam panels drop down to block outside air as a source.

So before I reinvent the wheel here has anyone tried to install HEPA cabin filtration over the two Evans Unit inlet ports? Most modern high end automobiles now have cabin filtration but it appears a high end RV is without this necessary component.

Actually sourcing the cabin inlet air directly above the generator seems like a very bad idea, filter or not. Would make more sense to get the air higher up on the front mask and duct it to the Evans Unit.

Fresh Air Position:



Recirculation Mode Position:

[Dutch Star Don]

If you're concerned about the air intake, just build a box over the two doors and slip a cabin filter into it. There is no bad air in the generator compartment since the exhaust is outside the compartment. You'll never have the generator running at the same time as the dash A/C when parked. If you run the generator while driving, the airflow from under the coach will dissipate any possible exhaust and heat from the generator.

[Winepress]

Key word “High end”
I bet a Newell would have such a filter.
I don’t think it would be too difficult to set one into the intake. We mostly run ours on recirculate. When it’s hot for the AC, really don’t want the outside air.

[bruceisla]

Originally Posted by Winepress

Key word “High end”
We mostly run ours on recirculate. When it’s hot for the AC, really don’t want the outside air.

Ditto ... I inserted a switch in the circuit to the engine A/C compressor so I can close the dampers via the Max A/C without running the compressor (when roof air is on).

[brobox]

I made one out of a a vent filter sold at Home Depot. https://www.homedepot.com/p/4-in-x-1...VENT/100351670
My inside A/C take the same filter so I had them on hand.

I used hooked Velcro on both opening, the filters stick to the Velcro. The filters are throw aways or washable. Easy to make, works great keeping the dust out of the MH.

[426smartin]

I like it

[turbopilot]

Originally Posted by brobox

I made one out of a a vent filter sold at Home Depot. https://www.homedepot.com/p/4-in-x-1...VENT/100351670
My inside A/C take the same filter so I had them on hand.

I used hooked Velcro on both opening, the filters stick to the Velcro. The filters are throw aways or washable. Easy to make, works great keeping the dust out of the MH.

Better than nothing. In the HVAC business this is called a “rocks and boulder” filter. I am talking about “HEPA” level filters found in high end autos. These filters handle pollen, fine dust and for us out West fine particulate from all the forest fires.

[Canuck53]

Originally Posted by brobox

I made one out of a a vent filter sold at Home Depot. https://www.homedepot.com/p/4-in-x-1...VENT/100351670
My inside A/C take the same filter so I had them on hand.

I used hooked Velcro on both opening, the filters stick to the Velcro. The filters are throw aways or washable. Easy to make, works great keeping the dust out of the MH.

What is the approximate size and do you have both sides covered? Is one the in and the other is the out?

[Finance]

Keep the intake closed, run a real HEPA filter system inside the cabin on the inverter.

[turbopilot]

Originally Posted by Finance

Keep the intake closed, run a real HEPA filter system inside the cabin on the inverter.

That is a work around but might also lead to freeze up in high humidity low temperature situations.

[pasdad1]

Originally Posted by turbopilot

That is a work around but might also lead to freeze up in high humidity low temperature situations.

Why would the coach have higher humidity than outside?

The roof mounted air conditioners always run in recirculating mode.

[bruceisla]

Originally Posted by turbopilot

That is a work around but might also lead to freeze up in high humidity low temperature situations.

There is a freeze detector (cold control/thermostat)
https://www.comfortairgr.com/shop/co...1061666-89101/

[Winepress]

Panel on my air system has two buttons that illuminate when pressed. One is recirculating the air and the other is the AC compressor. Maybe this is a new feature. You can stop the outside western smoky air from entering with the AC off or on.

[turbopilot]

Originally Posted by bruceisla

There is a freeze detector (cold control/thermostat)
https://www.comfortairgr.com/shop/co...1061666-89101/

Yes, and it exists to clear a freeze up. Simply shuts down the compressor when air in the Evans unit reaches 40F. There are many reasons to avoid extended operation in the recirculation mode. Refer to documentation.
.
The point of this thread was to determine if anyone has found an effective way to filter outside air of fine particulates, not figure out ways to work around what appears to be a significant feature lapse in a modern vehicle HVAC unit. My BMW has had cabin HEPA filtration since at least 2013. It would seem logical to have the same functionality in a $400k coach.