We are getting water in the bottom of our freezer. I took back panel off seen no problem tubes were frosty and checked later and bottom tube was red and melting the frost off rest of tubes making lots of water. Were to start??

If you have a pan in the very bottom of your Refrigerator, to catch the water when it defrost, this pan is actually under the refrigerator,there is a tube that drips the water into this pan and it is possible that this tube is stopped up, So clean it our the best that you can and see if this stops the problem.