Attention....Those With Heated Floors

[Dutch Star Don]

NOTE:....I won't be able to prove this information until I camp in cold weather again, but I'm guessing others are having the same issue.

We rarely camp in really cold weather compared to many who probably do back east. However, we like to go to Quartzsite every January and then loop around toward Sedona and the Grand Canyon. Last year and this year we hit weather in the teens and this year hit weather at Williams (base of Grand Canyon) where it dipped to 10 degrees overnight.

On a couple of occasions last year and once this year, the water line to the refer froze overnight. It's freezing where it runs under the FWS when extended. Luckily, it didn't do any damage and eventually started working again as the day warmed up. With help from others on here, they pointed out where the thermostat for the refer heated wire was located.

The thermostat is on the right wall of the battery compartment, up against the roof of the bay. On my coach, I have heated floors. Even in the 10-degree weather, my bays stayed in the 60's. The thermostat is directly under the main portion of the heated floors. "Rev. Roy" suggested, and I suspected that the floor heat was keeping the thermostat from coming on (ON at 40').

So.......I figured that the position of the thermostat may have just been an issue on my 2019 DS but spoke earlier to a friend with a 2023 DS and his is located in the same spot.

Obviously, if you don't have heated floors, not an issue. On the Freightliner chassis, there is an open-air space behind the battery bay and at the rear of the fuel tank. I moved my thermostat to that position. Unfortunately, I won't hit that cold of weather again until next year, to prove what I believe is happening.

Lastly, the thermostat has a red LED which means its off and a green LED which means it's on. It has a blue dot in the center which is the thermistor. To test the unit, I took a can of compressed air used to spray off keyboards, held it upside down and sprayed the thermistor. It shot cold air on it and immediately went to green.

[alank]

Isn't it fun when you have a 2019 coach, and just now are finding things that never worked properly.
I have a 2019 also and just this past Christmas when we were in 3* overnight temperature, we found out we never have had any basement heat. The whole coach and floors were heated, so the freeze up was a soft freeze, no damage but took most of the day with electric heater in the basement to have running water again. So, we were all set, the DW taking a shower, announced the drain wasn't working. Panic time, but after a few minutes, the brain light bulb came on and I removed the shower head from the hose and stuck the hose with hot water only down the drain, less than two minutes and the drain was open. What a relief.

[BayRunner]

Originally Posted by alank

Isn't it fun when you have a 2019 coach, and just now are finding things that never worked properly.
I have a 2019 also and just this past Christmas when we were in 3* overnight temperature, we found out we never have had any basement heat. The whole coach and floors were heated, so the freeze up was a soft freeze, no damage but took most of the day with electric heater in the basement to have running water again. So, we were all set, the DW taking a shower, announced the drain wasn't working. Panic time, but after a few minutes, the brain light bulb came on and I removed the shower head from the hose and stuck the hose with hot water only down the drain, less than two minutes and the drain was open. What a relief.

Coming from four season boating world, I’ve always been conscious of temperatures. This is why I have cellular temp sensors inside the coach and bay’s. I have them set to notify me by text and email when the temp gets to 35 digress. Saved one of my boats once when the main breaker flipped in 5 degree weather. This of course won’t help Don’s situation and has me wondering where the sensor wire is located in my Ventana. Will need to look into this.

[jacwjames]

I was in pretty cold weather in late 2021. I had installed tank heaters that would come on the system heat, controlled by a snap disc. Problem was that the indicator light for the system heat is in the panel above the passenger seat.

I got up several time during the night and never did see the system heat light on, which lead to very restless sleep (essentially none).

So when I got back home I bought a second indicator light and wired into the tank heater circuit so when the come on the light should come on.

But like you I haven't had a chance to see if it actually works, haven't camped in colder weather yet.

[oldcoon]

Question, was your oasis turned on? Unless I'm mistaken this is where the basement heat comes from at the 40° temp

[alank]

Originally Posted by oldcoon

Question, was your oasis turned on? Unless I'm mistaken this is where the basement heat comes from at the 40° temp

I have an Aqua Hot and it was providing heat for the coach. Both brands of hydraunic units are what provide basement heat. I have all the correct components, but wasn't plumbed or wired correctly from the factory.

[Dutch Star Don]

Originally Posted by oldcoon

Question, was your oasis turned on? Unless I'm mistaken this is where the basement heat comes from at the 40° temp

This has nothing to do with the Oasis system. The temperature sensor is located in the open-air battery bay. It's a separate unit that is powered all the time and turns on the heated wire when it senses temps below 40 degrees. In theory, the open battery bay should get cold enough to turn the sensor on. However, the bay gets heated by coaches that have heated floors.

Stuart, an old poster but new 2023 DS owner did a test this morning on his coach with heated floors. His coach floors over the battery bay on the INSIDE of the coach were 71 degrees. The outside air temp was 41 degrees. The battery bay, at the sensor was 57 degrees. 17 degrees above the temp it needs to turn the thermostat on, even though the outside temp was 1 degree above the thermostat trigger point.

[oldcoon]

OK, Sorry I mentioned it. My 21 MA is different then than your coach

[Dutch Star Don]

Originally Posted by oldcoon

OK, Sorry I mentioned it. My 21 MA is different then than your coach

No problem, you're right about the Oasis heating of the bays, but the refer thermostat is a separate unit. I didn't know anything about it or even what it looked like or was located until I hit some cold weather this week.

[BVJandJ63]

Originally Posted by Dutch Star Don

No problem, you're right about the Oasis heating of the bays, but the refer thermostat is a separate unit. I didn't know anything about it or even what it looked like or was located until I hit some cold weather this week.

Speaking of which, DS Don, do you have (or can you point me to) a picture of what the "refer thermostat" looks like? I can't seem to find a related image when searching on that terminology. Thanks!

[Wil_H]

Thanks, Don. I'll look for and relocate that thermistor. I'll second the need for a photo of the unit so we know what to look for.
Thanks again,

[Dutch Star Don]

Here is a good photo of it. When you look in the battery bay, it's up high on the right-side wall. The red LED is always on in normal operation. When the temp drops below 40 degrees, the red LED goes off and the green LED will illuminate. It's very hard to see, but there is white looks like a small blue dot in the upper center of the unit. That is the thermistor that senses the temp. I hit it with a spray of upside-down compressed air, used for cleaning keyboards. Using the can upside down produced enough cold air to illuminate the green LED as a test.

The unit has nothing to do with the Oasis or thermostat settings.

[BayRunner]

Originally Posted by Dutch Star Don

Here is a good photo of it. When you look in the battery bay, it's up high on the right-side wall. The red LED is always on in normal operation. When the temp drops below 40 degrees, the red LED goes off and the green LED will illuminate. It's very hard to see, but there is white looks like a small blue dot in the upper center of the unit. That is the thermistor that senses the temp. I hit it with a spray of upside-down compressed air, used for cleaning keyboards. Using the can upside down produced enough cold air to illuminate the green LED as a test.

The unit has nothing to do with the Oasis or thermostat settings.

Attachment 386326

So Don, you moved the whole unit in the picture to the empty space behind the Garry bay and fuel tank?

[Dutch Star Don]

Yes, unfortunately though, the wires were not long enough. It took some arm stretching, but I was able to reach in and cut the three wires and extend them by 18". I then moved the unit to the rear of the battery bay. I mounted it as low as possible, but still wanted to be able to see the LED's.

On a Freightliner, the cavity behind the sensor is open to the ground.