Hybrid electric/propane tank-less water heater

I think that the best solution would be to put an on demand propane heater in place of his tank type then find a space for a small 120v electric only heater in the line before it. That way the electric water heater will provide all of the hot water that it can with the on demand heater making up the shortfall. You get the best of both worlds.

Vegas Food Guy The reason I used 2 Gallons per minute is that is the flow rate for an Oxygenics Shower head or at least MNY oxygenics shower head.

I don't shower 24x7 Only for a few minutes at a time but if I were using an electric DEMAND heater during that time I'd need nearly 100,000 watts of power. Well beyond a 30 amp and in fact beyond mu 5,500 watt on board generator's abilit..

wa8yxm wrote:
To heat 2 gallons of water from 68 degrees to 100 degrees in one minute you need
9390 watts (equal to 9.39Kw / 32040btuh )
The source
A 30 amp rig has only 3600 watts and a 50 amp only 12000 I burn about 300 on parasitic loads. See the problem? (and up to 1000 if the batteries are hungry)

Clearly I'm not doing it with 120/240 vac.

If dry camping, this is a non starter, you will go through all your water in no time.

To heat 2 gallons of water from 68 degrees to 100 degrees in one minute you need
9390 watts (equal to 9.39Kw / 32040btuh )
The source
A 30 amp rig has only 3600 watts and a 50 amp only 12000 I burn about 300 on parasitic loads. See the problem? (and up to 1000 if the batteries are hungry)

Clearly I'm not doing it with 120/240 vac.

dougrainer wrote:

Octaneforce wrote:
I have the girard tankless hot water heater in my coach. Its hands down the best thing i ever did. I take boiling hot showers as long as i want. It doesnt seem to eat up much propane. And its only using propane while theres a call for hot water. It doesnt fire on and off all day like a regular tank heater. Their customer service is also outstanding.

If it is so great, WHY would you even know their Customer Service is outstanding??????????? A GOOD product will mean you will never have contac with Customer Service. Doug

PS. A Blind Hog will find an acorn. There are thousands of Girards out there and most work as designed. But, in my experience, the hundred or so I have seen over the years have operational problems. MORE so, Than standard 120/LP water Heaters.

I had to speak to them twice. First when i didnt realize theres a flow control so the water doesnt come out like a jet stream. They walked me thru how to adjust it, which is a peice of cake. Another time i had a freakishly cold night and i didnt add antifreeze to my water tank, and a fitting inside the water heater froze and busted. It was my own fault. But they mailed me a replacement part within days of contacting them, which i thought was awesome.

So yea these flash heaters do come with their quirks that an old school rv’er just isnt going to deal with. But for someone like myself who is stubborn in the opposite ways, i do my research and work out the kinks so now i have unlimited hot water which everyone (especially the wife) is thrilled with. I see it as one less thing anyone can complain about (as long as it keeps working).

Octaneforce wrote:
I have the girard tankless hot water heater in my coach. Its hands down the best thing i ever did. I take boiling hot showers as long as i want. It doesnt seem to eat up much propane. And its only using propane while theres a call for hot water. It doesnt fire on and off all day like a regular tank heater. Their customer service is also outstanding.

If it is so great, WHY would you even know their Customer Service is outstanding??????????? A GOOD product will mean you will never have contac with Customer Service. Doug

PS. A Blind Hog will find an acorn. There are thousands of Girards out there and most work as designed. But, in my experience, the hundred or so I have seen over the years have operational problems. MORE so, Than standard 120/LP water Heaters.

I have the girard tankless hot water heater in my coach. Its hands down the best thing i ever did. I take boiling hot showers as long as i want. It doesnt seem to eat up much propane. And its only using propane while theres a call for hot water. It doesnt fire on and off all day like a regular tank heater. Their customer service is also outstanding.

1. I am not aware of any 120/LP on demand water heaters for RV's.
2. On Demand usually requires 2- 120 Heating elements to supply enough heat for On demand. Only the Largest Aqua Hot type systems have dual elements. The smaller Aqua Hot types both LP/120 and Diesel/120, cannot supply on demand Hot Water(120 volt) for regular use.
3. After all the problems and complaints I have had from my customers in the past years, I would NEVER have a RV On demand Water heater. WE have replaced and also have replaced under OEM goodwill about 25 units over the past years from On Demand to regular RV Water Heaters due to customers hating the On demand. From bad operations to lack of continuous HOT water they wanted. Doug

^^^ Agreed.

A few years ago I looked at doing an on demand electric at our house. Just the cost of the additional wire I needed to run made it a non-starter.

On demand propane is a different deal. That's cheap and easy. Last year I bought a 3.2 GPM on demand propane for our deer camp, EBay, $64.00 delivered. Works great!

There is no way to do an electric "on demand" heater. A 50 amp RV only has 12,000 watts available. Propane does work.

I have a ten gallon electric/propane and it meets my needs.

On pure electric it takes 90 minutes to first cycle. Then it recycles once every 4 hours for 15 minutes. It draws 1400 watts.

I much prefer to run on electric--and save my propane.