Darcy Report post Posted April 18, 2009 I have an '07 Damon Tuscany 40-foot diesel RV. This is my third summer and after rinsing out the antifreeze, filling the HWT, turning on the gas, it lights up fine, but only lukewarm water comes from all taps. Checked for HWT air lock, shut-off valves in wrong position, lots of water pressure in both pump and city source. Share this post Link to post Share on other sites
wolfe10 Report post Posted April 18, 2009 You have already addressed the most common cause of lukewarm water, and that is a water heater bypass valve that is not completely closed. Also, check for any shower that could be turned on at the controls, and turned off at the head. That will allow hot/cold to mix in your system. When you do run the water heater, does it run the "normal" length of time to heat the water -- i.e., do you think the water is getting up to temperature in the tank but not getting to the faucets, or does the water heater shut off after too short of a run time? What brand/size water heater? Brett Wolfe Share this post Link to post Share on other sites
craver65020@yahoo.com Report post Posted February 6, 2010 I have same problem with my 2008 Fleetwood. This is the 2nd time. First time I had mixer valve replaced, it lasted 5 months and now have same problem again. Does anyone have any suggestions as to fixing this problem? Thanks Jim Share this post Link to post Share on other sites
AUGIEP Report post Posted December 14, 2011 I had the same problem with my Fleetwood Bounder. It turned out that the mixing valve located on the back of the heater was plugged with calcium buildup. I removed the valve completely and installed a remote Strahman mixing valve that allows you to adjust the mix of hot water and cold water. (the stock valve cannot be easily adjusted). The Strahman Valve has been working flawlessly and I have had ample hot water ever since. What's even better is that with the remote location, I can adjust the valve easily to raise or lower the water temperature with a simple turn of the dial. Share this post Link to post Share on other sites