Works as advertised but doesn't last as it should.
I live in the Colorado Rockies where it's certainly not hot - the fans rarely come on - and I drive <5,000 miles/year, but I got only about two years service out of the previous Derale 16789 before relay #1 got sticky and the fan would stay on until I rapped the controller with a small hammer. The innards of the controller are potted so there's no way short of cutting the cover off of the relay to get at the contact to burnish them. After a few years of lifting the hood every time the relay hung, I'm replacing the unit with the same part but installing external relays so that the fan current never passes through the controller -- I'd rather replace a five dollar relay than a $130 controller.
I'm replacing the thing with the same part because it's what fits my setup; otherwise I'd select a different product.Read full review
I needed a true fan controller and was delighted to see that a reputable company Was baking one that looked great. Upon receiving the controller I installed it following instructions exactly and was pleased to see it worked great for about a week. My engine ran hot and upon inspection discovered the fans were not coming on. I bypassed the controller using the manufactures instructions and both fans ran for about two weeks then quit. The unit is now completely dead and I have asked for a refund.I am sadly disappointed that’s such a simple item could’ve cost me my engine because it was nothing but junk.There are literally hundreds of reviews on this exact same controller with the same or worse performance. Steer clear save your engine buy something else.