Tankless Water Heater: Give Your Outback Shower Power!

Having hot water can make getting back to basics plenty more luxurious and super efficient!
1.Hot-water-makes-for-happy-girls

Say what you will about sliced bread and shirt pockets, for my money one of the best things ever has to be pressurized hot water—specifically, the kind that rains down on sore muscles at the end of a long day’s work. When we dove into the off-grid life, there were many modern conveniences we expected to do without. In fact, our intent was to strip life down to a near primitive level, find out what was really important to us and what was just clutter. Along the way, we discovered many things we could do without. Hot water was not one of them.

For the first couple of years we made due heating water on the wood stove or on our propane camp stove. We showered under a watering can hung up in the garden and bathed in an old washtub by the fire. On nice days, rinsing off in the garden was ideal, and the nasturtiums climbing the trellis loved the extra shot of water. Nonetheless, packing heavy tubs full of water proved to be time consuming and labor intensive. It didn’t take long before we were experimenting with other options.

One of our first attempts happened almost by accident. We had run several hundred feet of black poly pipe from the spring down to our tepee for non-potable water. With that done, I started work on a drip irrigation system for the garden. While doing so, I found that a 200-foot coil of 3/4-inch black pipe laid in the sun produced a steady stream of very hot water. Eureka! Soon the drip irrigation system was on the back burner while I worked on a solar water heater. This beat packing and heating water hands down, but was not without its drawbacks. Namely, the instant the sun went down, there was no more hot water. Not the best setup for gray, gloomy Oregon. Next, I tried a gravity-feed copper coil on a small rocket stove. This worked but required constant attention.

Over the next three years, we ran through a number of inexpensive, low-tech options. All of which offered limited success. With a new baby on the way, it was time to let technology into our forest oasis and, hardest of all, dust the cobwebs off the wallet.

Tankless Water Heaters
I had seen tankless hot-water heaters before. They work great and are very efficient. Instead of paying to keep a large tank of water up to temperature around the clock, they only use energy when the water’s running. The downside is that models made for indoor use are expensive and require some elaborate venting and plumbing. For us, this was out of the question. Undaunted, we kept digging. When we found some manufacturers that offer small outdoor models, we knew this was the hot ticket. One quick trip to the local RV store and a couple hundred bucks later, we had everything we needed for instant, flick-of-the-switch hot water.

When we got our new heater home and unpacked, I was surprised to find how simple it was. Basically, it consists of a small radiator sitting over a propane burner. When the system is turned on, a flow meter senses water flowing through the unit. Instantly it opens the internal propane valve and sparks the igniter to light the burner. In reverse, when the water flow stops, the propane valve closes—simple and very effective.

Beforehand I had built a small out- door washroom (“the shower shack”) from logs off the property and old barn lumber. A 150-gallon tank plumbed to the gutter for rainwater catchment provided the water source. To provide the pressure we needed, we used a small 12-volt DC pump, the kind used in RVs. The pump is wired through a switch to a large, deep- cycle 12-volt battery. A small 6-watt solar panel keeps a trickle charge on the battery. Next came the heater it- self. Simple garden-hose fittings con- nect the heater to the pump with a particulate filter in between. Then you connect the heater with the supplied fittings to a propane tank. All that’s left is to hit the switch, stand back and marvel at the hot stream of water shooting out!

We have been using this system dai- ly for a little over a year now. In that time we have only had to charge the pump battery twice off the generator. Through the summer months, the so- lar panel keeps up a good charge. The heater unit itself sips propane; the burner uses about the same amount as it takes to run a single stovetop burner on high. A 7-gallon propane tank will last for months.

Working Out The Kinks
The system is not without a few lit- tle quirks that are worth mentioning. First off, unlike more-expensive in- door units, all of the small outdoor heaters I have seen are “dumb.” They will not regulate temperature—this must be done manually. The output temperature is dependent on three things: the temperature of the water coming in, the flow rate and the burner setting. If the flow rate and burner setting remain the same and the in- coming water drops 20 degrees, the output will drop 20 degrees. If you increase the flow, the output temperature goes down and vice versa. The heater comes with a valve to control both the flow and the burner.

Another factor is the battery charge. As the charge goes down, so does the flow, and up goes the temperature. With a little trial and error, you will soon find flow and burner settings that are just right. One thing to be very careful of is starting and stopping the heater. Say, for example, you shut off the water momentarily to lather up then restart it. The water that’s been sitting still in the hot radiator is now super heated. This makes for a very unwelcome surprise when you turn the water back on.

Like any outdoor water system, you will want to take steps to protect it from freezing. A couple of well-placed drain valves in the system, on either side of the pump, will make this a simple task after each use. The fact that the heater nei- ther knows nor cares about the input and output temperature can also be an advantage. When our daughter, Samantha, was born, we had her at home. Some days before her birth, we had picked up the inflatable birthing pool from our midwives. It was a 150-gallon arrangement, similar to an inflatable raft but with the water on the inside.

Holding The Heat
For weeks leading up to the big day, I worried about how the little heater would perform heating such a large volume of water. As it turned out, the heater worked brilliantly! Within a couple hours it had filled the tub with 101-degree water. The big air cells in the tub acted as great insulation. Now the trick was to keep the tub at the right temperature over the next few days while we waited. My wife’s suggestion was both simple and brilliant. “Just drop the input line into the tub of already warm water and recycle it through the heater,” she said. We ran the heater like this every three or four hours, for five to 10 minutes at a time. This was more than enough to keep the water just right.

The midwives in attendance were so impressed with this that they are looking into purchasing a heater themselves. They told us several horror stories of folks with 20-gallon tank heaters that were never able to get the tub warm enough, let alone keep it there. By the time the tank heater recovered, the water in the birthing tub would already be cold. This experience has us thinking of other ways to use the heater. An old hot tub with a bad pump and heater could be brought back to life by using the tankless heater and pump in the same way.

Of the three different heaters we looked at, the Marey GA5 seems to rise to the top. This unit is made in Puerto Rico, offers a five-year warranty and supplies two gallons per minute at a price slightly less than that of the competitors. Close behind in a dead heat is the Ecco Temp L5 and Aquaking 6L. Ultimately, we went with the Ecco Temp since it was available locally. So far we have no complaints, except for the exceedingly cheap shower head attachment it came with that failed right away. Granted, this setup is far from a jetted tub at the Four Seasons. But pack enough heavy hot tubs of water to and from the woodstove, and your definition of luxury begins to flex considerably. When all is completely said and done, this setup is inexpensive to purchase and operate, saves us hours of time daily and fills a basic need admirably.

Wash-room-complete-with-a-Maytag-ringer-washer.

2.-At-3GPM-this-Shurflo-12v-RV-pump-proved-to-be-the-perfect-mate-for-the-tankless-heater.

3.-Notching-logs-for-the-shower-shack

4.-The-tankless-heater-came-with-all-the-plumping-and-shower-head.-The-pump-and-filter-we-purchased-seperatly.

  • Mark C

    Hi Will,
    After reading you article the first thing that came to mind is that you should install a “tempering valve” on your system. Not to be confused with a “mixing valve” which is what you have in the kitchen faucet. A tempering valve is an all mechanical device that installs on the hot water line just after the water heater. A cold water line connect to the second inlet on the valve and the outlet goes to the point of use. The valve is temperature adjustable and once set stays there. When water come in that is above the set point, the valve lets in cold to mix until the correct temperature is reached. This is a simple and relatively inexpensive device that works great and will prevent accidental scalding which is very important with a little one around.