I originally started this blog as a part of a project for my EMBA. At the time I was living in Indiana. Since then, I have changed jobs twice, and moved to two different locations – its been a hectic last couple of years. Due to my career and life changes, I abandoned my blogging. However, I have noticed a decent amount of activity and interest, so I am picking it back up with some current projects.
My next project will be a water box for a portable AC. I recently moved to the Portland, Oregon area, and found very few houses and even apartments have AC systems installed – due to the weather they aren’t needed as much as other areas. However, in a 3 story place, the 3rd story gets very hot. So, I decided to go with a portable AC unit for now.
For those of you who have never used a portable AC unit, the problem is that when you cool air it causes condensation, and water builds up. The AC units have tanks in them, and when they fill up they shut down. Then you have to roll it over to the bathroom, or someplace, pick it up and drain it out. So, instead of that, I am building a water box that the AC unit will drain into, and when the water level gets to a couple inches, I’ll have it pumped out the window.
Currently, I have the system functioning, but it is not complete. I have created my wooden water box – the wood inside has been stained with a polyurethane stain (PolyShades), and all corners/cracks have been sealed with a standard silicone. I have not finished the outside of the box yet (I am waiting to get my controls system finalized before I finish it). I am using a 12 VDC pump I picked up on Amazon ( https://www.amazon.com/gp/product/B00HR8MS7G/ ), a 5/16 hose from HomeDepot, an old 12 VDC adapter I had laying around, an Arduino Mega (an overkill, but I didn’t have any of the smaller boards on hand), and a 4 channel relay shield I picked up from RadioShack (You really only need 1 channel for this project, but the shield was just more convenient as it mounts directly on the Arduino – you can find some 1 channels cheap on Amazon https://www.amazon.com/WINGONEER-KY-019-Channel-Module-arduino/dp/B06XHJ2PBJ/ ).
I am running into issues with direct contact sensors – sensors that are sitting in the water. My first sensor I made from various parts, corroded very quickly. I am now using a water sensor I picked up on amazon ( https://www.amazon.com/gp/product/B01N058HS6/ ). The sensor worked well, but it is picking up some corrosion/scaling, which is causing indication issues. I’m not sure whats causing the issue, as I figured the condensation would be fairly pure water, but I am assuming it is coming from either the polyurethane, the silicone sealant, a combination of the both, or even maybe a reaction of the urethane and the silicone.
Due to the direct-contact sensor issue, I am going to switch to a non-contact method, using an ultrasonic sensor, which you can also find online at Amazon, such as these https://www.amazon.com/Keyestudio-Ultrasonic-Distance-Measuring-raspberry/dp/B01K4D1TQG/ . I am busy working, but I should be able to complete this modification next week, and will have more to post with some better pictures, code, and directions.
Picture of the AC unit on top of the water box:
A picture inside of the water-box. Don’t mind the messy wires – that was caused from changing sensors out, and some uncertainty of success. You can see the pump, and the sensor (red circuit board towards the bottom). You should be able to see the corrosion/buildup on the lower portion of the sensor: