Dear Janet,
I have given your various questions a considerable amount of thought and I have some items I need clarification on and some safety concerns I need to share with you.
Concerning: Question #1 – How hot should the outside of the box get with the door closed?
Answer - The access door will be hot to the touch as it is how the exhaust gases are vented to the outside of your Atwood water heater. I WOULD recommend you be cautious when working around this area as it is very hot and Safety should always be the 1st thing we are concerned about whenever we are working around the propane and the flame of any appliance.
Concerning the flame “rolling” back out of the burner tube and up toward the new circuit board. Yes you do have reason to be concerned….this is a safety issue and things do not appear to be operating correctly.
Let me say….If you have any concerns about how to properly work on this water heater, I would strongly suggest that you have it serviced by a qualified RV technician.
If you are comfortable and feel you can work on this unit safely please proceed with caution and perform a Burner Assembly Cleaning Procedure on your unit. I suspect the U tube burner assembly that houses the burner and ignition probe has a clog in it. Insects such as wasps, bees, love to take up housekeeping in this dark and cool area. Once you light off the flame the wasp nests and other debris is trapped inside the U tube. If you have not performed a cleaning on this U tube, feel free to contact me and I will walk you through the procedure.
Question #2 – How hot should the water get before it turns off?
Answer – The thermostat is designed and preset to turn off the circuit board at 140 degrees Fahrenheit which turns off the flame that is heating the water in the tank.
Question #3 - Smelling LP gas in the bath room
Answer – You have shared several things that have been done to this water heater. I noticed in your questions and information that you have recently changed out the thermostat (t-stat), ECO (emergency or energy cut off) switch, thermal cut off switch, circuit board, wiring assembly and electrode.
This is a lot of work and there could be several things contributing to the problem of smelling gas and the unit operating all the time as mentioned in Question # 2.
How long has it been since you drained the water heater tank? Sometimes if the tank is not drained on a regular basis the mineral deposit build up will cause the inside of the tank to be lined with calcium and other minerals to create a “blanket” that limits the heating of the water in the tank
Also, when the new T-stat and ECO switch were installed are you sure that they are making good contact the outside of the tank surface. If they are not secured and touching the tank, then the T-Stat is not sensing the correct heat of the tank, which in turn tells the circuit to keep the flame on and continue to heat the water. The foam pad cover must be securely in place helping to hold the T-Stat and ECO once they have been put in place
The other issue that could affect the water heater not turning off could be caused by the T-Stat and ECO being reversed. Since the T-Stat cuts out at 140 degrees and the ECO cuts out at 180 degrees, if the wrong one in being used as a T-Stat that controls the power to the circuit board then the board is not being told to turn off the flame.
The ECO is on the left and the T-Stat is on the right. The T-Stat has brass colored male connectors and usually has a yellow dot between these connectors while the ECO has silver colored male connectors.
Concerning the smell of gas, since the time that all this work has been done on this unit, has anyone had a chance to verify that the rubber grommet that surrounds the copper gas line that feeds the water heater is in place? This grommet is located on the lower left hand side and is round and is used to seal around the copper tube that is supplying gas to the water heater. If by some chance it has been left off, there is the danger of any potential gas leaks that allow gas to enter the inside of the coach. We have found that sometimes when there is a change of air pressure on the outside of the coach – like wind blowing and there is a furnace blower or air conditioner blower operating that outside air and gases are drawn into the coach. I would suspect this water heater is located under a cabinet in or around the bathroom area.
If by some chance this grommet is missing then I would strongly recommend for safety reasons that it be replaced or it be sealed with silicone caulk.
I realize you have asked other questions (#4 -#8) but I believe the safety concerns should be addressed and the necessary repairs be made by a qualified RV technician or someone that is familiar with the proper repair procedures.
I would ask you get back with me as to what you have found with this water heater and if you have pictures of the repairs as they are being performed pleased send those as well so we can share them with others having similar problems.
Thanks Again for your Questions
Terry Cooper, the Texas RV Professor
