Propane tankless water heaters

[Rednecktek]

FWIW, I've gotten rid of all mine. I had a few issues with it in my climate that made just getting a propane 30gal worth it.

1: The cold sandwich trying to fenagle the flow rates and temp adjustments to get a comfortable shower was a bitch. It's not like you can just set the thermostat and walk away without spending stupid money.

2: It's impossible to have one mounted outdoors and not have it freeze and burst. Trickling water through would drain my well and then it would freeze up while I waited for the well to recover.

3: Unless you spend stupid money, the water has a hard time absorbing enough heat fast enough when it's below freezing outside.

4: The batteries for the igniters require more amperage than the USB-> D-Cell adapters can provide and the box is always right behind a pipe fitting.

The propane 30gal solved all the problems.

 

[hpeyerl]

I just bought a Rinnai RXP160in which has a built in recirculation pump and claims to support both propane and natural gas automatically.

I hated the many spikes in my solar assistant from my resistance heater and after thinking about the heat pump water heaters, I decided they're a bad idea and got the Rinnai. It's not installed yet though.

 

[Chicat]

I considered a propane tankless when were building our off grid home and was talked out of it by our plumber as according to him thet have quite a bit maintenance and don't perform as well at higher elevations were at 5800 ft. So we went the electric route with an 18 gallon 120V which uses 1500 watts for about 2 hours in winter and 45 minutes in summer.
No kids or long showers

 

[AH Trimble]

I considered a propane tankless when were building our off grid home and was talked out of it by our plumber as according to him thet have quite a bit maintenance and don't perform as well at higher elevations were at 5800 ft. So we went the electric route with an 18 gallon 120V which uses 1500 watts for about 2 hours in winter and 45 minutes in summer.
No kids or long showers

We got lucky or picked the right brand...We are at 5835' and ours does fine. Not a single bit of maintenance in 4 years.

 

[Zwy]

I saw a video on descaling. It looked pretty simple.

It isn't hard to do, just that it needs to be done. Similar to draining a tank type water heater to remove scale.

I do think heat pump water heaters have come a long way since first models. It is a mature product at this point. If you really want propane, I'd go with a powervent like the one in my house.

 

[Dave911]

I have a Richmond natural gas unit. The same unit is available in propane.
Its a beast.
I think this is it.

Richmond® Encore® High-Efficiency 9.5 GPM 199,900 BTU Tankless Natural Gas Water Heater

The popularity of oversize tubs is growing, and so is the demand for large volumes of low-cost hot water. The Richmond Encore Tankless provides a compact solution for a continuous supply of energy-efficient hot water that won't run out. Why keep 40-50 gallons of water hot when you don't need it...

www.menards.com

Almost 10 GPM. Its a two pipe high efficiency unit. It heats up very quickly even when just running a sink.

Gas usage is insignificant.

I dont take long showers and its just me and the wife. But my wife likes to wash lots of stuff.
We have 2 1/2 bathrooms.

I had an electric tank heater. I still have it plumbed in in case this tankless died. It never has and I think its going on 4 years.

We have hard well water, but we have a dual tank softener which does a good job.

 

[Shawn Hayes]

We use a Navian propane tankless water heater. Ours has the built in recirculating unit. You can program the recirculating unit to run when you want it, that way hot water is close when you open the tap….
I’m on a well. I installed three filters, a sediment, a carbon and a descaling filter in front of the unit. However ALL of our water goes through the filter system before it goes into the house our water heater.
I absolutely love the unit and it saves on propane usage.
The unit I bought was setup for natural gas. However it came with a conversion kit to switch to propane. I changed it myself. Plenty of YouTube videos on how too.

 

[740GLE]

FWIW, I've gotten rid of all mine. I had a few issues with it in my climate that made just getting a propane 30gal worth it.

1: The cold sandwich trying to fenagle the flow rates and temp adjustments to get a comfortable shower was a bitch. It's not like you can just set the thermostat and walk away without spending stupid money.

2: It's impossible to have one mounted outdoors and not have it freeze and burst. Trickling water through would drain my well and then it would freeze up while I waited for the well to recover.

3: Unless you spend stupid money, the water has a hard time absorbing enough heat fast enough when it's below freezing outside.

4: The batteries for the igniters require more amperage than the USB-> D-Cell adapters can provide and the box is always right behind a pipe fitting.

The propane 30gal solved all the problems.

Not all tankless are outdoor units, so freezing can be avoided if your house is temperature controlled.

Also you can get portable out door units that run off just two D cells.

We’ve made do with an L10 Ecotemp plumbed into our camp for the past 3 years, it is finicky but I have it dialed in now it is manual control for flame and water flow so shower is priority. The wife likes high pressure showers so flow is low, so we have to then crack the bathroom hot water facet to bring temp down.

I want to snag one of those tanked heat pump retrofit jobbies marketed for converting from gas to electric, they run off 120v. They aren’t really designed to work beyond the south as they have no conventional heating element as back up.

Rheem Performance Platinum ProTerra 40 Gal. 120-Volt Plug-in Smart Heat Pump Water Heater with 10-Year Warranty XE40T10HM00U0 - The Home Depot

Introducing the Rheem ProTerra Plug-in Heat Pump Electric Water Heater. Like the Rheem Proterra models, this 40-gallon model is known for its high efficiency. The ProTerra Plug-in was created to make it easier to replace your natural gas tank with an electric model. Over 4.5X the efficiency of a...

www.homedepot.com

Seeing we’re not heating water past frost season, it’d be perfect for us and double up by helping cool the first floor of the camp when we run it. Sadly she says it’s too expensive (she ignores the federal rebate) so we’ll make do with the on demand.

 

[ASword]

Previous house had an NG tankless installed for hot water and heating backup. First unit died within two years due to condensation not making it out the exhaust chimney properly. Replaced with a newer unit which worked well until I sold the place a few years later. Had huge on/off problems until I added a recirculating loop with a pump, flow meter and microcontroller… not only did that fix the hot/cold cycling issue at low flow rates, but it was MUCH kinder to the valves in the unit. The unit would flip back and forth between 0% and 100%, but with the recirc loop it would slowly ramp up or down as needed. Did save a ton on the energy bills.

 

[dopeassjackson]

Here is my thinking on the propane vs electric question.

I had a propane dryer using $3 gallon propane every time it ran. Most times when Im running the dryer we are sending back to the grid and getting almost nothing for it.
Last year threw out the propane dryer and got a new electric.
very rare when I am buying electric to run it, and when I do, I only pay the 5 cent/kwh delivery charges with my electric plan

depends how much solar you have I guess... Propane aint cheap !!!

Yes. People tend to forget that if your replacing a electric appliance with gas your just moving where you spend your money. They make heat pump electric dryers also.

We use the wood stove to dry a ton of stuff in winter. In the off season we still hang the big things like pants and jackets.

 

[AKvalleyguy]

We have no NG available and use a propane direct vent for winter back up heat, infloor heat, and hot water domestic in the summer. Paying for propane in the summer is for efficient that starting a daily fire in the outdoor wood boiler. Most DV heater are not good for hydronic heating but the old Takagi units were. Recently replaced it for a newer unit and found that Takagi was bought by AO White. Lowes sells the AO White (Takagi) heaters. I got the 160k btu and it was around $1100.

I don't have the hot/cold issue with the setup because it runs through a Boiler Mate so there is that buffer some have mentioned.

 

[nc73]

Shouldn't you guys be adding more electric appliances? What will you do with all that solar? I must be the only one adding electric appliances vs replacing with gas.

 

[DevSecOps]

Shouldn't you guys be adding more electric appliances? What will you do with all that solar? I must be the only one adding electric appliances vs replacing with gas.

Electricity is not always going to be the best solution for many people. A good example, presented many times in this thread, is large amounts of water usage; households with a bunch of kids or family members or those who take long showers. A tank based electric water heater has 30/40/50/75 gallons, when you run out, you run out. Gas tankless water heaters are perfect for those types of households. We have propane fire places in various rooms. In the winter it's nice to be able to heat just a bedroom vs the entire house without having to install ugly mini-splits in each room or use very inefficient electric space heaters at times when the sun is normally down.

The same, but slightly different, kind of logic applies to those who work 8-5 jobs and drive EVs. They can't charge during the day via solar, so they pull from the grid at night to charge their cars. I'm not sure that spending $60k on sufficient battery storage would be the best use of my money to charge my 140kw Rivian battery every night.

My all electric house came with no gas or solar, and I've added both. They each have their purposes.

 

[AKvalleyguy]

Shouldn't you guys be adding more electric appliances? What will you do with all that solar? I must be the only one adding electric appliances vs replacing with gas.

Alaska around 61 N Lat. It would take a full solar farm to overcome little to no sun for a month.

It would cost even more to move to a more southern latitude.

 

[Rider]

Instead of tankless, consider a heat pump/hybrid water heater. Drops your power needs from 4500w to 600w (mine is closer to 450w), easily run off a power station. Down-side is that recovery time is much longer, so in a home with a lot of users, it may not be enough. Mine works out fine for me as hot water needs are minimal.

 

[Dave911]

Alaska around 61 N Lat. It would take a full solar farm to overcome little to no sun for a month.

It would cost even more to move to a more southern latitude.

Northern Indiana here. The cloudy season here severely diminishes solar for 2-3 months. Its the moisture off the great lakes. Grid and natural gas will be my backups. When they ran natural gas to our house I had them supply 2 psi gas. So I can run a serious generator and heaters in my shop. That was a good decision. No additional cost other than a regulator for the house.

I keep track of Fairbanks weather and other than 3 months, its not that different than northern Michigan. But those 3 months in Fairbanks is way, way too cold. And I like cool weather. But -30F is not just cold, its ridiculous.

 

[740GLE]

Instead of tankless, consider a heat pump/hybrid water heater. Drops your power needs from 4500w to 600w (mine is closer to 450w), easily run off a power station. Down-side is that recovery time is much longer, so in a home with a lot of users, it may not be enough. Mine works out fine for me as hot water needs are minimal.

As long as there’s heat to pull from.

In our basement it’s unheated until I get the wood boiler going. If I run the heat pump hot water heater in heat pump only mode in October, it’ll pull the basement temps to ~50f.

That’s why many hybrids have traditional heating elements as back up, and 120v only heat pump water heaters are only recommended in warmer climates.

 

[Lavarock7]

I bought a Rheem on-demand propane water heater on Ebay. They never installed it because it was not vented for indoor use. In my case it is mounted outside shaded the roof eave. I had problems finging the right propane regulator for it because most of the ones on island here are for propane grills and stoves and these need to delive lots less propane. The unit must be specifically stated for propane s the needles are different sizes. My unit worked flawlessly for years but now has an airplane noise which may be a buildup of minerals. Actually a better change of a gecko stuck inside I have not performed any maintenance on the unit in years, so my bad. Still, out electricity is the highest in the country so the $700 spent to buy it has been good.

Although not a problem for solar people, I wa on grid at the time and made sure that the power for the igniter, fan and board were powered with a UPS in case of a power outage. There is nothing worse to be in the shower, have a power outage and immediately have cold water. Remember Instant on can also mean instant off.

As we were biolding the downstairs rooms, we didn't really think things out. We used PEX (plastic pipe) which is great, but we daisychained the items one to another. It would have been better to use the spike idea to have shorter runs t othe hot water than waiting longer at the end of the line.

The propane water heater also helps us in another way. We have a propane tank available if we need to lug it over to the propane/gasoline generator to suppliment power t othe house of charge the batteries.

I would not mind having a larger on-site propane tank but having it filled by a company is difficult to get a truck to the house. We also get earthquakes here. We had a 6.9 and an hour later, a 6.2 about 30 miles north of me

 

[AKvalleyguy]

But -30F is not just cold, its ridiculous

Yeah, way too cold. We are north east of Anchorage and our local area is oddly warmer than most. -F temps are rare and cold at my location is +5 to +15F.

We have no service except for a phone line. To get natural gas would be a dream. Glad you have access to is, hauling propane tanks is something I'm looking to stop doing. Heating fuel is much easier to deal with. But for today, propane it is.

 

[teal95]

For northern climates electric only just doesn't work. There arent many sunny days in November and December and even when there is one the sun is low enough on the horizon that I don't capture much. Vertical panels certainly help but it's still not enough.

 

[AKvalleyguy]

In our basement it’s unheated until I get the wood boiler going. If I run the heat pump hot water heater in heat pump only mode in October, it’ll pull the basement temps to ~50f.

In the winter, you are right on. You gotta pay for heat one way or the other. Summer time would work, unfortunately it's way down on the project list. Wood boiler though .

 

[740GLE]

In the winter, you are right on. You gotta pay for heat one way or the other. Summer time would work, unfortunately it's way down on the project list. Wood boiler though .

Yup the water heater gets about 5gal of water of condensate each week in the basement helps keep it nice and cool.

Wood boiler does heat and DHW needs from Nov till March/April just gotta spend a week or so spring and fall cycling aged/green wood around. On year 12 I have it down to a science.

Also now having the mini split for heat, allows up to avoid burning heating oil.

 

[AKvalleyguy]

Also now having the mini split for heat, allows up to avoid burning heating oil.

That's something I need to try, a mini split.

Sounds like we have a similar wood burning cycle. I start in October but usually stop in late Feb, early March. So much sunshine, typically, I run electric heaters to burn the excess solar. A mini split would be better than resistance heaters, Then deploy the extra solar to water heating or something. With a business and "homestead" to run, things get done in slow motion out here.

Suggestion to the OP on tankless propane. I have 100 lb tanks and a 200 lb "mini pickle barrel" the full sized pickle barrel tanks are 420 lbs, I think. The pickle barrel tanks are easy to move with a tractor. I do not like 100 lb tanks, have to hand dog them around and they weigh about 170'ish pounds when full.

 

[Zwy]

For northern climates electric only just doesn't work. There arent many sunny days in November and December and even when there is one the sun is low enough on the horizon that I don't capture much. Vertical panels certainly help but it's still not enough.

I have my heat pump water heater in series ahead of the propane water heater. In winter, if no sun is forecast for long periods, I will turn off the heat pump water heater and turn on the propane water heater.

Putting the two water heaters in series gives 100 gallons of hot water storage for 97% of our hot water usage. We don't run out of hot water.

Think outside the box. Add more panels if needed. A heat pump water heater will use 3 Kwh per day. In Alaska, mid winter, yes, there might not be enough generation. If your location gives about 3 peak sun hours in winter, it only takes 1 Kwh of generation per hour to power a heat pump water heater for a day. Three 400W panels can cover that.

 

[teal95]

HPWH is pulling it's heat from somewhere, that I then have to make up for.