Warm but not HOT water

[BobTheBuilder]

2011 Bighorn with a SW12DE Suburban water heater. Used coach that is new to me. In electric mode only, water gets to 108 degrees and no higher. Can't find anything in the manual or forum regarding trouble shooting for this. With gas it is only 115 degrees which means we use very little cold water for a shower and it doesn't last long. My two previous SOBs got so hot with gas operation that several could shower and they were smaller tanks.

Also in gas mode I have something of an orange flame but they won't tell you how to clean it in the manual (liability purposes I am sure). Does anyone have any hints or must I have a "qualified technician" check it?

 

[John T Bettencourt]

Had same problem with my Landmark and it was the plastic check valve on the water tank. What happens is it get stuck and let's cold water in. You can take it out and free it up or do what I did and replace it with a brass one.

 

[WillyBill]

Here are a couple of "Checks"
Verify Anderson valve in UDC is all the way to normal position and not partly to "winterize position".
Verify bypass valves on back of water heater have been returned to correct position(not bypassing)
Verify outside shower has valves all the way off.

 

[mlpeloquin]

Did you adjust the amount of air that is sucked into the chamber? There is an air adjustment aperture for the flame. Another thing, make sure the outside shower has both cold and hot knobs off, otherwise you will get mixing of the hot and cold and never get the hot water that you should.

 

[cookie]

Make sure that the water heater bypass and the winterize valve are both in the "Normal Flow" position.
Also make sure that the outside shower faucets are turned off.

Peace
Dave

 

[danemayer]

The Suburban water heater has separate thermostats for gas and electric operation; both preset to 130(F). So if you have less than 130 from both operations, it's probably not the water heater itself.

You likely have cold water mixing with the hot. As already mentioned, that can happen if 1) the water heater bypass is partially in the bypass position, 2) the knobs on the outside shower aren't closed, 3) the check valve on the hot output of the water heater is stuck open or broken.

Regardless of which it is, you should inspect the check valve on the hot output of the water heater. In the 2011 timeframe, plastic check valves were used and as the plastic ages, it can crack and leak. The longer the plastic valve is left in place, the more likely it'll be difficult to remove. There's a detailed procedure with pictures on how to replace the check valve, starting on page 14 of the Water Heater Troubleshooting Guide in this folder.

 

[BobTheBuilder]

Thanks to all. Shower knobs are tight and bypass was correct (I had checked it already) so it must be the check valve on the hot output of the water heater is stuck open or broken.

 

[TedS]

I doubt that it is the check valve. The only time cold water is on that valve is when the heater bypass valve is in the bypass position. I would suspect the thermostat or its connection to the control board.

 

[danemayer]

Ted may be right about the check valve not having cold water on it unless the water heater is bypassed.

Maybe the bypass valve is leaking cold water into the mix. I just replaced mine because when bypassed it was allowing a little antifreeze into the water heater tank.