Both cold & hot water at the sink is HOT.........?

[jbbcd]

Hello, I consider my self as a jack of all trades master of non.........now after this, I need to come up with a new saying......I`m feeling really dumb right now.

I just installed a Hybrid heating kit into my 6 gallon hot water tank. I did nothing with the water lines & followed the supplied directions to the T. So I was happy when I turned on the supplied on/ off switch and the water started to warm up (very slow). I then waited for approx 3 hrs for very hot water, too hot so I turned the thermostat all the way down to as far as it would go. I don`t want scalding hot water. By this time it was getting late, so I figured I'll leave it on all night & check the water temp in the morning. The next morning I turned on the hot water at the sink & it was scalding hot! I then turned on the cold water and that was scalding hot as well.......

1) I placed the thermostat onto the outer casing of the hot water tank so the thermostat is not touching the actual hot water tank? Causing the scalding hot water?

2) This is the one that makes me feel very dumb........how can both the cold/ hot water be hot?? when I did nothing with the water lines? 

[richard5933]

My presumption is that the thermostat has to be in direct contact with the tank in order to function.

Just a guess on the cold water heating, but if you got the water that hot perhaps it built pressure. With the extra pressure the path of least resistance might have been back into the cold water circuit.

[wolfe10]

Most RV's have a check valve so hot water can not "back up" into the cold system.  Yours may be bad.

Not familiar with the device,-- I would contact them to troubleshoot it.

[jbbcd]

update.....last night the outside temps dropped down to 30 degs....I think the out side water line froze. I turned on the house water pump & then the cold water did get cold.

That stinks, cause I don't think I can get direct access to the water tank? I'll have to start taking apart the surrounding cabinetry to get access? 

 

[wolfe10]

What RV do you have??

[jbbcd]

classic.....lol  1994 Chevy C Damon Hornet

[jbbcd]

 

looks like its an enclosed water heater so I will not be able to attach the thermostat directly onto the true water heater  wall....

Ill have to trick the thermostat some how?? not sure what to do at this point to keep the water from getting too hot.... Glad it didn't blow up last night!

[jbbcd]

[rayin]

There should be a small removable cover over the thermostats. Often it is black, others are the same metal color as the exterior. I don't know of any non-replaceable thermostats on a water heater of any type.However, if you are adding a electric heating element, there may not be a place for that thermostat.

The over-temperature/over-pressure relief valve should open when water temperature is too high. It may require replacement also.  It i looks and acts exactly like the one on your home water heater. It you cannot get to the actual tank to attach the thermostat, how about the flange the relief valve screws into? Hopefully the jacket has an opening large enough to stick the 'stat into, Then hold it in place with a piece of insulation.

 

[kaypsmith]

5 hours ago, wolfe10 said:

Most RV's have a check valve so hot water can not "back up" into the cold system.  Yours may be bad

I'm with Brett, betting on a bad or no check valve. Easy to test, remove cold water to hot water heater, blow into the hot water outlet side of the heater, if check valve is working, you will not be able to blow towards the tank, if missing, simply add one to the inlet side, doesn't have to be next to the heater, only close. Any store that sells plumbing has them in almost any size needed.

[jbbcd]

Thanks every one! Yet again I did something dumb......I turned the temp dial to max heat by mistake....I turned the thermostat down to the desired heat I like now. I'll be fine tuning the water temp for my wife too....

Thanks again for all your input!