Has anyone rebuilt one of the GF air filter system cartridges? There must be a better option than throwing it away. Given the weight, it’s a carbon based system… 20+ lbs and looking at it, it has a pleated filter, then the carbon, then a liner at the bottom.
Thanks… I pulled my first one apart and replaced the charcoal with about 30-35lbs, retaining the material at the bottom and vacuuming out the top filter. I’ve been using a pre-filter since getting the AFS so my top filter is in decent shape… and I’m not sure the best way to replace it… the charcoal was the easiest and it’s doing the bulk of the work.
Yeah the charcoal is really important for toxicity, as I’m sure you know. I wonder if there’s a easy way to empirically test whether or not your charcoal is working properly? A way to know when it’s time to replace it?
When I studied this a couple of years ago, folks were weighing the charcoal from time to time and there was a calculation that helped you determine, but I purchased a .5 micron counter from Banggood for around 35 and it tells me. Well worth the to be safe, especially with me rebuilding it.
You can disassemble it and clean/replace each of the filter layers. I have finally ordered a replacement, after almost 10 months, so I have a spare on hand because I feel replacement time is nearing. When I finally have to replace mine, I will be disassembling and refurbishing it.
Thanks… I need to source some charcoal to use… I found 40 pounds on Amazon for $90 but it was pellets, not granulated. Also, GF has some round piece mixed in with the charcoal… do you know what that is?
If you find a good source for activated charcoal, please pass it along.
OK, doing some research it looks like there are various ways, but I only remember baking as a viable way to clean carbon. The most reasonable process seems to be baking the carbon in a single level on a baking sheet for 1 hour at 300 degrees. Does this sound about right?
Also, have you been able to determine what the round pieces are in the GF air filter mix?
Thanks for the tip on cleaning it! I did not think it worked, so I bought… I’m going to take apart my second spent cartridge and bake the charcoal and give it a try, but please let me know if 1hr at 300 is correct.
I would do this in a very small batch at first to be sure that it doesn’t ignite. Apparently carbon can ignite at widely varying temperatures, I doubt you want a mound of activated carbon catching fire in your oven.
Further, if this is supposed to drive the volatile (harmful) compounds out of the carbon, that means that your oven (and soon thereafter your lungs) will be exposed to them, yes?
Since the charcoal collects mostly aromatic particles, personally, I would rinse the charcoal in clear water before drying and then baking. 300° for an hour should be good. Pleated elements are typically cleaned by a combination of vibration and vacuuming, lightly racking the filter against a hard surface, like a workbench should do, followed by vacuuming from the intake side then the exit side last.
Thanks and agree… That makes sense and I’ll do it outside on the gas grill. I’ve read from multiple companies that washed carbon in a conventional oven at 500 degrees will not flare up, so I will rinse it first, which will put some moisture in it. Flare up could be caused by the dust, so washing would help.
This is almost always a good approach when you need to heat something in the oven that might be a problem in the oven. I do my acrylic warming for bending or slumping and even annealing in the gas grill. Just make sure you’ve got a good thermometer - the standard grill ones are often error-prone.