TransWikia.com

Is a peltier-based dehumidifier a good choice to prevent condensation?

Home Improvement Asked on December 9, 2020

I have a non-heated, enclosed space (crawl space that does have a vapor barrier). During a limited number of days in the spring or fall, I get condensation on things that stay cold while the air warms up. I have tried leaving the vents open and closing the vents, and that doesn’t completely solve the problem since air motion is not guaranteed. I’m not interested in self-closing vents. Thus I am considering a dehumidifier.

My purpose for the dehumidifier is to reduce humidity from near 100% down to non-condensing on slightly colder objects, so maybe 85%. In other words, I don’t need to make it “comfortable”, just prevent condensation. The temperatures where condensation has been experienced range from maybe 40 degrees F to 60 degrees F (5C to 15C).

I’m sure that I could use a standard, compressor-based dehumidifier and achieve the results I want, but those are more expensive to buy and more expensive to operate than the peltier-based dehumidifiers. But I’ve read that:

the optimal operating temperature (for peltier dehumidifiers) is 59-86°F. It will not work below 41°F

So my use case is below optimal range, but still in range for some level of effectiveness.

My question is: does anyone have direct experience or professional expertise to advise on using one of these “cheap” dehumidifiers in this way (not the typical use, which is to make a room “comfortable”, but rather just take the humidity down away from the range that condensation occurs)?

One Answer

Peltier elements need 2 separated air (or water) flows on the cold and warm side. Even if those elements are run with only 20% of the rated current, the installation effort, space and power consumption will be still much higher compared to the solution of re-using an old PC fan and a small old plug-in power supply.

That power supply should be available in one of the next drawers or boxes with redundant electronics, and a low voltage fan could be harvested from an old PC. Hair dryers normally do also use low power motors, but mostly 20V or more. All should be also available for no or minimal cost at the next recycling yard. If the fan is a 12V type, any voltage between 7 and 12V should be working well. Hair dryers anyway have a 50% switch where the fan's voltage is reduced accordingly.

From a similar question:

An alternate method avoiding high electricity bills and the water drain for the dehumidifier: Installing a fan of an old PC at the Luv side, connected to a small power supply from an old phone or similar and a timer. If the fan runs only in the night, it pushes in statistically colder and dryer air. In 1 or 2 weeks the space will be much dryer. Electricity cost below 1$ per month.

Answered by xeeka on December 9, 2020

Add your own answers!

Ask a Question

Get help from others!

© 2024 TransWikia.com. All rights reserved. Sites we Love: PCI Database, UKBizDB, Menu Kuliner, Sharing RPP