Forum Discussion

rodjburge's avatar
rodjburge
Explorer
Dec 06, 2017

water heater replacement

In my 1999 endeavor, the hot water heater has begun to leak. Would assume that it is rusting out and needs replaced. It is an Atwood 6 gallon model mpd 93756. Has anyone had experience with replacing? Cannot find this exact model, what is the new replacement model? Is the new model pretty much interchangeable ?
  • It will be as long as dimensions are equal to what you now have. I swapped my water heater last year model for model and it only took me a couple of hours.
  • Your Atwood will have an aluminum tank so it shouldn't be able to rust.
  • Most Atwood leaks are at the fittings which can be tightened/replaced at nominal cost - make sure your "leak" isn't something readily fixable.
  • I was hoping to find a leaking fitting but it seems that the water is coming from the bottom of the tank, although it is really hard to see into this area. Even with an aluminum tank do these ever corrode enough to leak...after 20 years?

    Another weird observation.....I noticed what looked like engine coolant hoses (like what takes the engine coolant to the dash heater) and found in the original installation paper work that there is in fact 2 hoses that are routed to the motor of the coach. Not much in regards to explanation in the manual other than "hook up the coolant lines". Is referenced to as "heat exchange".
  • Looks like you have a heat exchanger which is even more possibility for a fitting leak. Hard to say leak is from the bottom because where ever it's leaking from it will run down hill. Try you isolate it and pressurize, gives you time to try and hear air escaping rather than having water run everywhere.
  • Coolant from motor is shunted to a heat exchanger around the hot water tank and normally on back to a heater under the bed. My hot water exchanger started to leak badly so I bypassed it. Check to see if it is engine coolant that is leaking, That's my bet. Bill
  • ScottG wrote:
    Your Atwood will have an aluminum tank so it shouldn't be able to rust.


    They will NOT rust, but the Aluminum can corrode and get pinholes from mineral deposits in the tank. Doug
  • Gjac's avatar
    Gjac
    Explorer III
    rodjburge wrote:
    I was hoping to find a leaking fitting but it seems that the water is coming from the bottom of the tank, although it is really hard to see into this area. Even with an aluminum tank do these ever corrode enough to leak...after 20 years?

    Another weird observation.....I noticed what looked like engine coolant hoses (like what takes the engine coolant to the dash heater) and found in the original installation paper work that there is in fact 2 hoses that are routed to the motor of the coach. Not much in regards to explanation in the manual other than "hook up the coolant lines". Is referenced to as "heat exchange".
    What make MH do you have? I know that vintage Winnebago's had that kind of heat exchanger to heat the hot water when driving. Also put some toilet paper under each fitting to make sure it is not leaking from the fittings. Both of my leaks on my Atwood were from the fittings in the back, any leaking water will run to the lowest point.