Here is my dilemma.

I am looking for a 5 gallon Water Heater to heat water prior to a preheated system reaches where I need the hot water.

No one has Propane 5 gallon water heaters for homes that I can find.

I see a lot of Tank-less Water Heaters

Will a Tank-less Water Heater work with a Preheated system.

I plan on Building a Solar / Wood Water Heating System and have a large Heated Water Storage Tank in a separate area other than my Kitchen Building and Bedroom with a Bathroom on it (separate Buildings) for my off grid place in Arizona.

Any help would be appreciated

For one that small, consider an electric. You can get them that run on a 15A circuit.

I've never seen a gas type htr that small.
You said "prior" to a pre heated system,but asked if ,it will work with a preheated system.How much are you trying to raise temp prior to the pre heat?

These work good for low volume 4 gallon

www.homedepot.com/p/Rheem-MiniTank-...=&source=shoppingads&locale=en-U

I saw an off-grid homestead type place where the lady owner had rigged a salvaged 7 gal. RV water heater to supply her bath and kitchen sink (also salvaged from an RV). The vent terminus was the issue she had; it was venting and procuring combustion air from the same space, putting itself out. Properly done, against an outside wall, it would work. No inspectors allowed.

Heating 5 gallons won't get you much for long.

Probably only 2.5-3 gallons of hot before it's not doing any good due to fresh cool water coming in.

My plan is and i have already started building a wood burning Pre Water heater.
I have not decided if I want to go with an heated antifreeze into a Solar System Water Heater or just have a circulation pump circulate the Water in and out of the 50 to 250 Gallon Storage tank.
Later i will add a Solar Water Heating system.
This Solar Water Heating system is one of the reasons that I am considering the Antifreeze.
This way I will not need to drain the Water out of the System during the colds winter months.
The Antifreeze would be circulated threw manifolds running around the wood stove pre heater and the Solar heater.
then that heat would be transferred to the water in the large storage tank.

Since my preheat system will be far from my buildings needing the hot water I was thinking about the small water heater attached to the outside in my structures on the out side with a cabinet built around them to protect the Heaters from the elements.

Doing this will give me immediate hot water to my structures and will only need to finish heating the water that traveled from my bulk storage tank.

The temperature in the bulk storage will very do to the sun and or fire in the stove for the preheat.

I was thinking Propane because the grid is 7 1/5 miles away and more than likely will never make it all the way to my place in my life time.

I could build up my Solar Electric System to have an Electric water heater but that make take a lot of money up front.

There are a lot of If's in my plans and i have a lot of Brain farts before I get down and dirty buying stuff and building what i came up with.

As Rock said, there are five gallon heaters that run on 15 amps.

Scavenge a Propane water heater from a junk RV- - - - -they're designed to mount with the burner on an outside wall so they draw combustion air and vent from the atmosphere outside the coach. I've got four of them at the moment on rigs that will never be on the road again. Back before I moved back to America, there were dozens of derelict RV's around the Salton Sea area, left over from snowbird campsites.

Maybe Recirculating pump?

As Rock said, there are five gallon heaters that run on 15 amps.

You don’t want a tank. You want a tankless, it will only come on if the water temp incoming is below the set temp of the heater(IIRC). If that is not the case, anyone with process and control experience could set it up that way. That is what I plan to do when I build my next house soon. Solar collector thermosiphoning to an elevated tank in summer, a wood-fired solution during freezing weather. The tankless will simply be a backup if the other solutions are not functioning for some reason. I can size the holding tank to my liking, and have as much hot water on tap as I might wish to.

I am looking into the feasibility of placing the solar collector inside a green house, and potentially using the collector as a radiator when the wood source is in use, to help heat the greenhouse.

Since this is an off grid project electric capacity might be limited?

This helps me a lot
I was wondering about the Tankless heaters and how they may or may not turn on and off whith the incoming hot water.

Thanks

That