Furrion Tankless Water Heater - Cold Weather

**WhittleBurner** · 10-30-2023, 04:14 PM

You flip it and it bypasses the water heater. There should be a section in your manual on it . I'm not familiar with the on demand water heaters to advise any further but I'm sure someone else can help

**JLA956** · 10-30-2023, 09:00 PM

Originally Posted by 4x4dually

We've wintered our Reflection with the Furrion tankless for several years now. I've always used compressed air to clean it out and have (knock on wood) never had any issues. Just be sure and pull the little black plug and drain anything left after the blow out. I always leave my nautilus valves halfway between positions after the blow out as well. That way they don't hold water on one side or the other with vacuum. Everything should drop with gravity and nothing should be left in the valves to separate them...or at least that's my take on the deal and to this day have never had an issue. You watch, now that I say this, something will break. First hard freeze of the year is tonight for us. LOL

Just to make sure that I understand your routine regarding "I always leave my nautilus valves halfway between positions". So, you place the water selection valve halfway between the City Water and Fresh Water Tank positions?

**4x4dually** · 10-31-2023, 06:38 AM

Originally Posted by JLA956

Just to make sure that I understand your routine regarding "I always leave my nautilus valves halfway between positions". So, you place the water selection valve halfway between the City Water and Fresh Water Tank positions?

I force air and let it run for a long long time in all positions then when I'm done, I turn all the valves, including the one you mentioned, halfway, yes. In my mind, it breaks the suction on the side that is closed so that any water left at the valve will drop with gravity down into the piping. The piping can flex with a little ice, the crappy plastic valves can't.

This is something I came up with on my own and wan't instructed by any OEM to do so. Use your own risk, but it makes perfect sense in my mind. The only thing I might consider is letting it sit for a few hours then turning them back on direction of the other. I guess it makes sense to not leave the valves halfway so that the seals don't get wonky on the inside from the halfway position. That just now crossed my mind.

**Soundsailor** · 10-31-2023, 08:26 AM

Originally Posted by KIMandALLEN1988

Does anyone know if I need to keep an active water supply (water pump on) to the Furion water heater in order for the anti-freeze protection to function? Does it need fresh pressurized water coming in, or does it recycle the small amount of water it stores in the unit?

While I don't know the official Furrion position on this, I always try to turn off the pump in my coach unless I'm using the water system. Should a leak occur, I really wouldn't want the pump to keep water flowing to the leak when I'm not able to detect it.

On our coach, we have the Furrion FHW09AM, so probably an older model than yours. We've had no issues camping in overnight temps in the 20s, sounds like that matches your experience. I think you'd be fine unless the temps get lower and stay lower especially if as you say "we will leave the tank pads and furnace operating while sitting at our house and while traveling."

**COGrandDes** · 10-31-2023, 09:20 AM

I know I upgraded my Furrion TWH motherboard to the revised one with "freeze Protection" and it does not require a water pressure source to operate. As long as I have shore power or battery power, and propane gas available, the Furrion unit will cycle on it's own to heat the water in the chambers to protect itself. I've actually watched it happen several times as the temps got lower before I winterized.

**Capn_AJ5** · 01-09-2024, 02:58 PM

@COGrandDes Thank you for this post. I have been searching for a while now to determine how the upgraded Furrion TWH worked while on the road traveling in temperatures below freezing.

We raised enough cane w/GD just after our purchase and learning about the 39° barrier to have our TWH replaced by GD AND we received proper winterization instructions with the new unit. And then I realized there were no instructions on what to do when traveling in freezing temps.

I'm happy to hear you have tested this feature. I was about to order a 12v heater/fan with a thermostat to plug in and have running while we are traveling (in Texas) in freezing temps.

**KIMandALLEN1988** · 01-09-2024, 05:07 PM

Originally Posted by Capn_AJ5

@COGrandDes Thank you for this post. I have been searching for a while now to determine how the upgraded Furrion TWH worked while on the road traveling in temperatures below freezing.

We raised enough cane w/GD just after our purchase and learning about the 39° barrier to have our TWH replaced by GD AND we received proper winterization instructions with the new unit. And then I realized there were no instructions on what to do when traveling in freezing temps.

I'm happy to hear you have tested this feature. I was about to order a 12v heater/fan with a thermostat to plug in and have running while we are traveling (in Texas) in freezing temps.

We recently traveled from Indiana to rural Nevada with many days below freezing with snow on the ground. While it is not what we originally ordered, our Furrion tankless water heater functioned flawlessly. I have much more confidence now it its cold weather/cold travel use.

**gto1970** · 01-14-2024, 10:30 PM

I have a new 2024 grand design that is plugged into 30 amp at all times . with the furrion tankless water heater . I leave it at our ranch where it gets in the twenties at night . I always shut off the water pump , propane tanks and open the all the faucets and shower and power off the thermostat When we leave for the week . I only use the trailer on the weekends. Yesterday when I showed up I heard some some sound in the tankless water heater around 7pm . I put everything into operating mode meaning I turned on the propane , water pump etc , powered on the thermostat and went to take shower and the water would not constantly stay hot . It went from hot to cold . Later next day we had hot water and it worked flawlessly all weekend.

**Soundsailor** · 01-15-2024, 01:27 PM

Originally Posted by gto1970

I have a new 2024 grand design that is plugged into 30 amp at all times . with the furrion tankless water heater . I leave it at our ranch where it gets in the twenties at night . I always shut off the water pump , propane tanks and open the all the faucets and shower and power off the thermostat When we leave for the week . I only use the trailer on the weekends. Yesterday when I showed up I heard some some sound in the tankless water heater around 7pm . I put everything into operating mode meaning I turned on the propane , water pump etc , powered on the thermostat and went to take shower and the water would not constantly stay hot . It went from hot to cold . Later next day we had hot water and it worked flawlessly all weekend.

If the temps are getting into the twenties at night, and there is no heat in the coach, it's quite likely that the water in the heater is freezing. While you appear to have dodged any damage so far, I'd recommend using a compressor to blow out all the water lines including the water heater in between uses.