Atwood water heater temp adjustment?

[Free Ranger]

I have the Atwood GCH6A-10E hot water heater on my 2018 Navion. Of late it sounds as if the water is almost boiling in the tank when it kicks on in electric mode: lots of popping and crackling noises that's a bit unnerving in the middle of the night right under the bed. I don't remember ever hearing before this winter. The pressure relief valve has never popped off or weeped at all. The manual is not very helpful in answering the question as to whether this model has a temperature adjustment feature.

Any thoughts out there or similar experiences that you've solved?
Thanks

FreeRanger

[DavidM]

I don't think that the temperature setting is adjustable. I turn mine off after taking a shower and turn it on again about 15 minutes before needed it the next day.

David

[imnprsd]

I assume this technology has not changed in 20 years! If so, the thermostat and ECO touches the tank. It's located behind the black foam tape square if you still have one.

It's just a normally closed (NC) switch that opens at ~145F. So maybe if it's not making contact, or if the contact is oxidized, which is probably the problem, then you just need to clean it with some fine black sand paper (1000 grit), or you may need to replace the thermostat. (ECO too while you are at it.)

I carry a spare. And don't forget to use a protection diode. (See last picture.)

https://www.amazon.com/Thermostat-As...6535346&sr=8-5

TIPS

==> When installing the ECO and T-stat, be sure to position the spring so it mates against the plastic protection piece (works like a dielectric plate) and does not SHORT out. ...You sometime need to bend the metal tabs just a tad so you can twist everything in place.

==> If you find your hot water pulses out of the shower after camping for 2 to 3+ weeks, changes are you lost your "air gap" in the tank. To fix this, just turn off the water pressure in the hose, turn off your pump, and open the emergency overflow valve.

[Free Ranger]

Great input! I'll give that a try and thank you.

[Morich]

Something that can happen might be worth some thought. When electric heating element are used, they can tend to dry minerals on the element and if it get a good thick coat, they can pop and crack as the element heats up. Think of a thin layer of rock (limestone) cracking?
So it might be worth a bottle of vinegar runs through the lines to clear some of the scale off the tank and element?

A test of the thermostat might be done by using a thermometer to check the water temp to see if it is way high?

[Tallman]

Just so people are aware - The "ECO" thermostat on the left is supposed to open at about 82C (180F) and is an emergency backup to the "normal" thermostat on the right that is set for about 60C (140F). They are marked with the temperature on the side that faces the tank. If the ECO thermostat opens, the system is "locked-out" until the power is cycled. The problem in my brand new (May 2021) 2108DS Micro Minnie (with Dometic WH-6GEA water heater) was that both thermostats were 60C and the one on the "ECO" side usually tripped first. That points to a quality control problem at the Supplier.