Anyone build or buy engine dehumidifier?

[6896]

Your sketch looks plausible. This is essentially an oversized version of the Barker aquarium pump design. In the Barker plans, the aquarium needed to be modified to seal it's plenum from the outside air. I used sintered metal filters from McM Carr (they come in different diameters) to keep dessicant particles or dust from entering the system. Your sealed box could be a plastic storage bid with the type of tape using for vacuum sealing films on composite molds such as sold by AC Spruce. The only thing that might need to be considered is overheating of the compressor inside the box if it ends up running for any period of time. If it is low horsepower, this may not be a problem.

McM Carr sells some low flowrate air pumps at https://www.mcmaster.com/air-pumps, albeit they are pricey, but they are totally sealed with an inlet and outlet. They battery powered too. You may be able to find some less expensive ones on eBay or Amazon.

I noticed that there are much larger aquarium pumps than the one I used in the Barker kit that may be a good compromise. See Amazon link below.

https://www.amazon.com/dp/B071DV12S3/re ... 31060f34e0

Also, a canister vacuum cleaner is another possibility as a pump as it has high flow at low pressure, and one could adapt to the air filter inlet to close the loop.

Finally, another idea, how about an inexpensive, hand held heat gun? You could disconnect the heating element and just use the fan. The heat gun inlets may be more adaptable to sealing to make the system closed loop, thereby avoiding the airtight box for the compressor. Inexpensive ones are less than $40.

Good luck.

[8322]

My concern with a heat gun would be that i think thats an axial fan inside, axial fans create the most cfm per watt but the air they move has little ability to "work" as in make its way through ducts and such... id also fear a floor vac or heat gun isnt really designed to run 24/7 and are loud... though the heat gun with no heater may work great for the initial blow out of the nastiest air right after shutdown as it wouldnt have to run through tubes and filters...

[8322]

I built one, I'll post pics. I went closed loop... I put digital hygrometer in the pump tub, it records 24 hour high and low. Right after hooking up it went up to 57 and has dropped under 45% since, today ambient was 85+%, so it is keeping rh down, though I'll admit I hoped for 30's... but pulling from almost 60 to low 40s ain't bad I suppose...

Though inside engine may be 30s as the dehuey is cold and engine is warm right now... preheated before last scheduled flight that got cancelled, so left it on till next flight. I will say it keeps it hot! When I pulled dipstick to hook up dehuey the oil was not warm it was hot... I didn't realize they got em that warm...