[RegaNewell]

Well I was told when I bought my Coach from an Individual, that the heat exchanger was for extra transmission cooling.  I was also shown were the switch was located to turn it on and only needed it when pulling a heavy trailer.  So for the last 10 years, until I read this thread this morning, this is what I thought to be true. I had to pull this unit out a couple days ago to get to an air leak above it.  I lowered the unit, and broke the fitting loose and out came red fluid, that I just assumed was transmission fluid. I assumed since the transmission was lower then this line that it would suck air and not siphon out all the fluid from the transmission.  So I walked away and let it drip.  About 30 minutes later, Pam hollered and told me to look under the coach.  I immediately started crying and was hollering for the kitty litter. Everyone that knows me understands, that I am still trying to realize the world still turns, even when you stain your concrete. After putting down 200 pounds of oil-dry, I got back underneath and tightened both lines back up. Then I thought the best thing to do, since I was completely soaked in fluid was to work as fast as I could and get both lines unhooked and pushed up to the Coach floor (higher then the transmission). I now had fluid running down both arms, chest and face, after about 5 minutes the fluid stopped flowing.  I am so happy that I stumbled upon this thread.  I now know that this is not a transmission cooler and that my hydraulic tank is now completely empty.  The only time I have heard these fans on the unit come on, is when I manually turn them on with a switch mounted in the very top left corner of the wiring bay inside the engine compartment. I now realize that I am going to have to completely understand how this system is supposed to work, and why mine has to be manually switched on.  I am including pictures of the mess, the unit and wiring relays.  What type/weight fluid is used in this unit?  I also have a non-labeled switch mounted on my dash, next to the HWH unit.  I was told this was used to switch the main hydraulic fan in low or high. It also looks like I will have to learn how to attach pictures correctly and in the right order.