Electric tankless point of use water heater?

[TheDonger]

Am I out of luck? I currently have the standard 10 gallon propane/electric water heater that works great, but it requires short showers. I’m staying in sites with full hookups so electric is preferred. I got the idea that I could jerry rig an electric point of use tankless water heat in the bathroom and connect it to the shower. The I found that all of these things don’t use a regular 120 wall socket and the electrical supply would get complicated. Does anyone here know a solution for me? I want limitless hot water and not have to fill propane when I’m at an RV park. I’d also like to maintain the dry camping hot water capability it has now. Is there a silver bullet?

[bigb56]

Since there is no way you can instantaneously heat water for a shower without using gas or a high amount of electrical current you won't find any plug in models for what you want to do. Without getting too technical it's all about temperature rise and flow rate, and unless you shower under a dribble of water, or are camped where groundwater is already warm it just can't be done without gas or high current. A typical current draw to heat water for a typical shower at typical groundwater temps would be 40 to 50 amps at 240 volts, definitely not a plug in. As the flow rate decreases or the incoming water temp rises the required energy drops.
10 gallons of hot water would be a luxury for us, we only have six gallons but with Navy showers it's been plenty. I think your only solutions are going to be a gas tankless, shorter showers or maybe a more restrictive shower head.
You could always go with a gas tankless and extend-a-stay if you stay in one place long enough and have the means to transport the large propane cylinder.
Then there is a saying over on the van forums, "A one gallon shower is a thousand times better than no shower" so you are not out of luck in that sense.

[Mudfrog]

OP, I wonder if there's something wrong with your 10 gallon heater? I would think it should be capable of giving you a good 10 minute non stop shower. This especially if you run propane and electric at the same time.

Ours is only a 6 gallon heater that supplies water for the 3 of us. Admittedly, we don't take long showers but it does well enough to allow us to all take our showers inside of an hour. This with only an electric 450 watt heating element energized. I honestly can't remember the last time we turned on the propane burner to heat the water.

[bigb56]

Originally Posted by Mudfrog

OP, I wonder if there's something wrong with your 10 gallon heater? I would think it should be capable of giving you a good 10 minute non stop shower. This especially if you run propane and electric at the same time.

Ours is only a 6 gallon heater that supplies water for the 3 of us. Admittedly, we don't take long showers but it does well enough to allow us to all take our showers inside of an hour. This with only an electric 450 watt heating element energized. I honestly can't remember the last time we turned on the propane burner to heat the water.

I wondered about that too. Getting the water hotter would also provide longer run times. I've never heard of a 450 watt WH element before, are you sure that isn't 1,450? 450 watts would take an eternity to heat 6 gallons of water. I know mine is 1,400 watts and heats it in about 20 minutes to an acceptable level but probably takes 30-40 minutes to bring it to full temp.

[Mudfrog]

Originally Posted by bigb56

I wondered about that too. Getting the water hotter would also provide longer run times. I've never heard of a 450 watt WH element before, are you sure that isn't 1,450? 450 watts would take an eternity to heat 6 gallons of water. I know mine is 1,400 watts and heats it in about 20 minutes to an acceptable level but probably takes 30-40 minutes to bring it to full temp.

I installed an aftermarket element called the "Hott Rod" about 19 years ago. It's rated at 450 watts but I believe the newer ones sold these days are rated at a lower 400 watts. It's not fast to heat water initially but it does seem to keep up fine after the water reaches set temp.

Things I like are that it has an adjustable thermostat and it doesn't draw much power when energized. I set the temp to 120° when I installed it and haven't touched it since. The water heater on ours is an Atwood which doesn't have an anode rod. Not sure I would recommend it for a Suburban water heater since I believe the element replaces its anode rod.

[Old-Biscuit]

Combo Gas/Electric 10 gallon water heater should be capable of supply hot enough water for 2 back to back showers

Suburban heats to 130*F -----gas/12,000btu & electric/1440W
Atwood heats to 140*F -----gas/10,000btu & electric/1400W

Gas & Electric can be turned on/used at same time for fastest recovery time.

[amosnandy]

Originally Posted by bigb56

Since there is no way you can instantaneously heat water for a shower without using gas or a high amount of electrical current you won't find any plug in models for what you want to do. Without getting too technical it's all about temperature rise and flow rate, and unless you shower under a dribble of water, or are camped where groundwater is already warm it just can't be done without gas or high current. A typical current draw to heat water for a typical shower at typical groundwater temps would be 40 to 50 amps at 240 volts, definitely not a plug in. As the flow rate decreases or the incoming water temp rises the required energy drops.
10 gallons of hot water would be a luxury for us, we only have six gallons but with Navy showers it's been plenty. I think your only solutions are going to be a gas tankless, shorter showers or maybe a more restrictive shower head.
You could always go with a gas tankless and extend-a-stay if you stay in one place long enough and have the means to transport the large propane cylinder.
Then there is a saying over on the van forums, "A one gallon shower is a thousand times better than no shower" so you are not out of luck in that sense.

Ok, so I just read through all the previous posts. How long do you want to stay in the shower? Wow. My previous coach had only a 6-gallon hot water heater and even with the pump on so it had 45 psi you could take 10-minute showers. Yes, on electric only, from ambient temp to 120 degrees took 45 minutes or so. I stay a lot in Mexico with only 30 amp service so frequently used the gas option. A few years ago I had friends visit and so 3 of us took showers in the evening with gas and electric, 10-15 minutes between showers nobody ever said their shower was not hot. I tend to agree that if you're not getting a 10 minute shower something is wrong.
I traded up to a DP with a 10 gallon water heater and have figured out a way to plug into 2 30 amp outlets and can leave the electric on all the time. It used to be I had to have the propane truck come every 5-6 weeks, but this year using mostly electic to heat water, I've not had to fill in 6 months.
Remember. You are camping. Not the Holiday Inn.
The only true on demand continuous hot water in a MH that I have ever seen work is an Aqua Hot, or one of its equivalents. And that just burns diesel.

[TheDonger]

It’s the second person that suffers. I guess a 10 minute shower should be long enough but I prefer longer. It’s disappointing that there isn’t an electric tankless option for campers.

[Lantley]

My thought is something is wrong with your heater. I have a 10 gallon LP/electric water heater. I have never run out of hot water and we do NOT take Navy showers.
Occasionally if groundwater is extra cold I may rum LP and electric at same time but for the most part it is electric only and we always have ample hot water.

[TheDonger]

Originally Posted by Mudfrog

I installed an aftermarket element called the "Hott Rod" about 19 years ago. It's rated at 450 watts but I believe the newer ones sold these days are rated at a lower 400 watts. It's not fast to heat water initially but it does seem to keep up fine after the water reaches set temp.

Things I like are that it has an adjustable thermostat and it doesn't draw much power when energized. I set the temp to 120° when I installed it and haven't touched it since. The water heater on ours is an Atwood which doesn't have an anode rod. Not sure I would recommend it for a Suburban water heater since I believe the element replaces its anode rod.

So it sounds like the “Hott Rod” element is in addition to the existing element? Or is it a replacement?

[TB673]

Lantley mentioned the extra cold ground water as 1 possibility, we (among others on this forum) draw off of the Fresh Water Tank thus tempering the water that you use.
Also we (again among others on this forum) use an OXYGENICS shower head.

With a 10 gallon HWT on electric only, the wife and I can take back to back showers without running out of Hot water.
Here is a link to Oxygenics:


https://oxygenics.com/search/RV+Shower+


much cheaper than a new HWT.


Tim

[TheDonger]

Originally Posted by Lantley

My thought is something is wrong with your heater. I have a 10 gallon LP/electric water heater. I have never run out of hot water and we do NOT take Navy showers.
Occasionally if groundwater is extra cold I may rum LP and electric at same time but for the most part it is electric only and we always have ample hot water.

The site I’m currently at has well water and it’s definitely cold. I’m currently leaning towards installing a propane tankless heater.

[bigb56]

Originally Posted by TheDonger

It’s disappointing that there isn’t an electric tankless option for campers.

It's not because nobody wants to build one, it's because logistically it's not possible. Making heat and making cold are two things that require a lot of energy, and heating water instantly takes a tremendous amount, as much or more than charging a Tesla although for a shorter duration. Another poster mentioned the Aqua hot which is a good idea if your rig is diesel but they do make propane tankless units that are installed on many new trailers including Airstream, but do your research, not everyone has great things to say about them.
When we used to have customers that didn't have gas in their homes but wanted instant hot water for the whole house the units used four 40 amp circuits and were capable of pulling up to 160 amps, we had to install bigger electrical services just for that.

[Old-Biscuit]

Originally Posted by TheDonger

So it sounds like the “Hott Rod” element is in addition to the existing element? Or is it a replacement?

No it's an aftermarket electric heating rod that goes in the drain hole on gas ONLY water heaters to have electric option

DO you turn on Propane & Electric for showers?



Question:
When was last time you drained/flushed your water heater?
Electric element could be scaled/calcium build up interferring with proper heat transfer.
A Vinegar Soak can clean up the element and tank
Pour 7 gallons of vinegar/3 gallons of water into empty water heater (remove T&P Relief Valve)
Turn water heater on....using electric element (or propane)
Let WH go thru 4-5 heat/cool cycles (do not use any Hot water)
**WH On overnight
Then drain/flush water heater (remove drain plug and turn water source on letting it BLAST out drain hole