I accidentally dropped a long piece of nylon cord into my hot tub, and it got sucked into the pump through one of the little holes in the top of the filter. I turned off the pump and yanked at the cord; some broke off, but it looked like I didn't get it all. The pump sounded different. I emailed Aleko tech support; they said it might pass on through but I might have to take the pump out. I turned the pump on for a moment and it sounded strained, so I turned it off. Tech support sent me to a Youtube video to see how to pull out and replace the pump and heater assembly. I followed the instructions for pulling out the pump and heater assembly, but I was on my own for getting into the pump. It turned out to be fairly straightforward, just a few screws, although some were a bit hard to reach. I opened the pump and there was the cord, wound around the little turbine (photos attached). I pulled off the cord and put everything back together, and the pump and heater work just fine. The heater and pump assembly case is some kind of plastic, held together with screws. Most of the screws are self-tapping into holes in the housing; be careful not to overtighten them. I added a bead of silicone caulk around the cover of the electronics module; I don't know that it was necessary, but it seemed prudent. I took some cellphone pictures along the way to guide me in putting it all back together again, since there is no manual or Youtube video for it. It took about two hours, but most of that time was figuring out what went where. Tech support answered my email in one day and was helpful.