EZ Scrub Cleaner
I have been brewing on an all-electric system for quite a while and cleaning the stainless steel heating element has remained troublesome. The baked on residue was hard to get off. I tried many things to make cleaning the element easy and effective and all were what I considered failures since I wanted the element shining like new. But the combination of failures led to a simple, cheap, no-hand-scrubbing solution.
In the beginning, I tried soaking the element in a hot PBW solution in a tall narrow container and then used assorted brushes to scrub it. I imagine many electric brewers are still doing this and I did it quite a few times. This was difficult, time-consuming, and had less than perfect results.
I then built an enclosure to protect the electrical connections on my tri-clamp element and ran it through the dishwasher. The enclosure was just a large empty plastic food container with a screw on lid (see picture below). I used a bolt-on tri-clamp fitting on the lid of the enclosure. This was a total failure since the enclosure leaked a bit because the lid didn’t seal well and the element didn’t come very clean anyway.
Next, I thought it would be clever to build an ultrasonic cleaner using parts ordered off the internet. The ultrasonic transducer and driver circuit board are surprisingly inexpensive. Ultrasonic cleaners use a transducer that converts electrical energy into high frequency mechanical vibrations. The vibrations are transferred into the cleaning solution where they create cavitation bubbles on the object thereby cleaning it. I tried a system running at 40 kHz and rated at 60 Watts.
I epoxied the ultrasonic transducer to a stainless container (sold as a vase) and connected the diver circuit board (see picture above). I also added extra sealant around the solder on the base of the vase. However, the vase was not well matched to the transducer for power transfer. I think the area of the base of the vase was too small to vibrate enough to transfer the energy properly. This resulted in little transducer energy being transferred into the hot PBW solution in the container. Most of the energy was reflected back into the transducer making it HOT!
I combined the knowledge gained from previous failures into a system that actually works with no scrubbing by hand! By using a hot PBW solution, a suitable tall container, and an aeration wand with an aquarium air pump running, the hard to remove baked-on film on the stainless heating elements slides off by itself after about 30 minutes. The bubbles seem to do all the work. I just do a bit of rinsing at the end to get it all off. The idea to try the aeration wand came from the ultrasonic cleaner failure. Even the wand gets a cleaning in the hot PBW as a bonus and other small items such as dip tubes can also get simultaneously cleaned in the process.
