Atwood hot water heater thermostat question

[tallpall888]

My hot water, which operates only on electric, gets too hot and I wish to cool it down a bit. I would like to order a thermostat that will activate (open) at a temp that is ten degrees cooler than what it does now. Have seen the adjustable units on ebay but would like to spend a lot less for just a fixed temp unit. The modules for sale on ebay seem to be the standard replacement ...and don't mention what temp they are set for. Can someone point me to an ebay thermostat that would fit the bill? Thx for any help!

Edit: googling found that Atwood thermostats are set at 140 degrees from the factory so I will look for a 130.

[DFord]

https://www.amazon.com/Atwood-91470-Thermostat/dp/B00A2TEBT0
Atwood 91470 Thermostat at Amazon $12.35

[wa8yxm]

As I understand you can get both 120 and 140's for Atwood. Check with a Sticks and Bricks. not an online supplier. Look for part # 91470

[rrupert]

dougrainer wrote:

tallpall888 wrote:
True...and we have had no problem with lack of hot water with this 10 gallon unit. There *is* a problem with the safety valve blowing occasionally and this is the second valve for that heater so the thinking is there is a problem with the thermostat letting the water heat too much. Replacing with even the standard temp sensor might have helped, but I don't anticipate the 130 degree unit I just ordered ($10 ebay) will be noticed.

The Pop OFF valve RARELY fails. What you have is a diminished AIR POCKET
in your Atwood tank. Doug

PRESSURE-TEMPERATURE RELIEF VALVE Weeping or dripping of a pressure-temperature relief valve while the water heater is running DOES NOT mean it is defective. This is normal expansion of water as it is heated in the closed water system of a recreation vehicle. The Atwood water heater tank is designed with an internal air gap at the top of the tank to reduce the possibility of weeping and dripping. In time, the expanding water will absorb this air. To replace the air follow these steps: Step 1: Turn off water heater Step 2: Turn off incoming water supply Step 3: Open the closest hot water faucet in the coach Step 4: Pull handle of pressure-temperature relief valve straight out and allow water to flow until it stops. Step 5: Allow pressure-temperature relief valve to snap shut, turn on water supply and close faucet.

I agree the air gap has to be there to absorb expansion of the heated water. I think you will find that the manual for the water heater instructs you how to do that.

[dougrainer]

tallpall888 wrote:
True...and we have had no problem with lack of hot water with this 10 gallon unit. There *is* a problem with the safety valve blowing occasionally and this is the second valve for that heater so the thinking is there is a problem with the thermostat letting the water heat too much. Replacing with even the standard temp sensor might have helped, but I don't anticipate the 130 degree unit I just ordered ($10 ebay) will be noticed.

The ECO on your unit is at 180 degrees. Going from 140 to 130 is NOT going to stop your problem. Reinstalling the AIR GAP will. Doug

[tallpall888]

I ordered this one: https://www.ebay.com/itm/Atwood-91470-Water-Heater-T-Stat-Thermostat-130-Degree/114021153414?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649
Thank you all for your attention!

[dougrainer]

tallpall888 wrote:
True...and we have had no problem with lack of hot water with this 10 gallon unit. There *is* a problem with the safety valve blowing occasionally and this is the second valve for that heater so the thinking is there is a problem with the thermostat letting the water heat too much. Replacing with even the standard temp sensor might have helped, but I don't anticipate the 130 degree unit I just ordered ($10 ebay) will be noticed.

The Pop OFF valve RARELY fails. What you have is a diminished AIR POCKET
in your Atwood tank. Doug

PRESSURE-TEMPERATURE RELIEF VALVE Weeping or dripping of a pressure-temperature relief valve while the water heater is running DOES NOT mean it is defective. This is normal expansion of water as it is heated in the closed water system of a recreation vehicle. The Atwood water heater tank is designed with an internal air gap at the top of the tank to reduce the possibility of weeping and dripping. In time, the expanding water will absorb this air. To replace the air follow these steps: Step 1: Turn off water heater Step 2: Turn off incoming water supply Step 3: Open the closest hot water faucet in the coach Step 4: Pull handle of pressure-temperature relief valve straight out and allow water to flow until it stops. Step 5: Allow pressure-temperature relief valve to snap shut, turn on water supply and close faucet.

[dougrainer]

ggardne2 wrote:
Just for info most Atwood/Dometic water heaters have a front mounted thermostat that controls the 12V propane circuit and on the back of the heater there is a second thermostat that controls the 110V element. If you only change the front thermostat it will impact the propane temperature but will have no impact on the electric element temperature. Unless you have a rear access panel or access to the back of your water heater you will need to remove the water heater to access the thermostat for the electric element (at least on any Atwood I have experience with). You can verify this information by reviewing the wire diagrams in the manual to your water heater.

Atwoods more than 15 years ago had 120 and 12 volt(LP) tstats. Since then they use just 1 tstat for both modes. Doug

[DFord]

I haven't tried this adjustable thermostat but it's the only alternative offered that I know of. I think the OEM stats keep the water close to 140 degrees



https://www.rvtravel.com/video-how-to-install-an-adjustable-water-heater-thermostat/

[ggardne2]

Just for info most Atwood/Dometic water heaters have a front mounted thermostat that controls the 12V propane circuit and on the back of the heater there is a second thermostat that controls the 110V element. If you only change the front thermostat it will impact the propane temperature but will have no impact on the electric element temperature. Unless you have a rear access panel or access to the back of your water heater you will need to remove the water heater to access the thermostat for the electric element (at least on any Atwood I have experience with). You can verify this information by reviewing the wire diagrams in the manual to your water heater.

[Dusty_R]

Many years ago I put an adjustable t-stat on our water heater. I don't remember how long it lasted, maybe only a couple of years, but it didn't last.
Maybe today they will last longer. Go ahead and try it, just keep the original with you so you can put it back in if the new one dies.

Dusty

[tallpall888]

True...and we have had no problem with lack of hot water with this 10 gallon unit. There *is* a problem with the safety valve blowing occasionally and this is the second valve for that heater so the thinking is there is a problem with the thermostat letting the water heat too much. Replacing with even the standard temp sensor might have helped, but I don't anticipate the 130 degree unit I just ordered ($10 ebay) will be noticed.

[Dave5143]

This maybe? Assuming it's an Atwood unit. I ordered one for my rig but haven't installed it yet.
Disregard this post if you've seen this one already. I just re-read your original post.

[cavie]

turn down the hot. turn up the cold.

[RJsfishin]

I always had the same problem w/ all my attwood heaters. I replaced the 140s w/ 120's still plenty hot. I got them at the RV parts places for about 20 bucks.