Propane Hot Water Tank heater or Tankless? Help me decide.

[TnAndy]

I was faced with replacing my tank model propane couple years back, so I turned to my neighbor who runs the QC section for American Water Heaters, local branch. He said after extensive testing, they had determined that tankless models DO NOT save energy over tank models with a standing pilot light. The pilot light keeps the tank water up quite a bit over normal incoming water temps. Only exception to that was if you have a 'get-away cabin' and are only there infrequently. Then go tankless.

He stated the only advantage to tankless was the savings of floorspace IF that was an issue.....and the disadvanges of computer controls that are expensive to replace if they go out was also something to consider.

I went back with a tank model.

 

[ZFish]

look into the heat pump water heaters. cuts the electric use dramatically, and does not curtail hot waster use. can be stand alone or add on. initial cost vs cost of use is the deciding factor. When parents lived in Florida they had the AC tied to the hot water, which was endless and a waste produt of the AC

The electric heat pumps are about 1000$ but save a ton of money. The work the best with a warm basement. 50degrees or so. The hotter the better basement that is. And it saves a ton of money on the elec bill. The generator load im not sure about you would have to do the math

 

[BeezFun]

I got an estimate to replace my conventional gas hot water heater with a tankless, what a shock. It couldn't vent out the same flue as my furnace so they would have to install a separate flue. Vent material was very expensive, tank was very expensive, I didn't see any way given my gas bill that I could ever see a payback in my lifetime. So even ignoring the quirks of a tankless it made no sense in my case.

 

[JoeinTX]

Beez, that sort of lines up with what I've heard on tank versus tankless. I've been told that if your current home is set up with a traditional tank then it's not worth it to try to replace with a tankless for the very reasons you list. Modifications to get it to code, materials, labor, etc.

Now on the other hand if you're building new then I've been that a tankless system is the way to go.

 

[wjmst]

I am considering swapping out my 40 gallon electric for a propane fired solution. Here is my situation:

My thinking is this:
- My going from electric to propane will save me considerably in energy costs and it will allow my generator to power the whole house without having to manage power loads like we do now.

What do you consider considerable energy costs? Have you calculated your current cost with the electric hot water tank? For me personally, I calculated my 40 gallon hot water tank to cost be about $1 per day, that was a few years ago when it was just my wife and I and we worked all day. I should probably recheck the calculation now that my wife is home with our daughter. I do not consider $1 a day for hot water too expensive.

 

[dave1949]

What do you consider considerable energy costs? Have you calculated your current cost with the electric hot water tank? For me personally, I calculated my 40 gallon hot water tank to cost be about $1 per day, that was a few years ago when it was just my wife and I and we worked all day. I should probably recheck the calculation now that my wife is home with our daughter. I do not consider $1 a day for hot water too expensive.

Good point and what I was wondering too.

You would need some cost comparisons to make a good choice. Our old water heater was an indirect fired type, a remote (30') zone off the propane fired boiler. It used ~245 gal. of propane per year for two people, 60 gal. SuperStor tank. I don't think the remote zone was very efficient, but your use would be double ours.

Electric or NG rates are a lot more stable than propane. One decent fluctuation in propane prices can wipe out any predicted savings. If I were thinking of relying more on propane, I would first get the propane cost stabilized; large owned tank, pre-pay, or whatever it takes. In the end, you don't have that much control over the pricing.

An electric water heater's usage can be offset by a grid-tied solar system if that is an option, it's one that gas will never give you.

The generator capacity is a small issue considering how often you need to use it. Manual load management costs nothing in dollars. You could consider installing a switch on either the upper or lower element that would take it out of the circuit when running on generator power. Your recovery time will be longer, but you will have hot water.

You may achieve some decent savings by just upgrading to a new electric water heater. The Rheem Marathon models are good. Foam jacket from the factory.

 

[MotorSeven]

I went with tankless on my new construction but opted for an outside mounted unit to save money on the flue(flue was about $150, unit was $400) and to keep open flame out of the basement. Even thought the unit is supposedly protected from freezing, when the power goes out you lose that protection. I have to go down to the basement and shut the water off & drain it out of the lines through the basement sink during power outages. It's no big deal, but I should have mounted the thing in the basement and put in the flue.

As far as heat, the thing is awesome & wil take my 58 degree well water to 140. There is a delay to get hot water on long runs and it can be annoying to us instant gratification types. MechE1 is right about pressure sensitive since I have had to put a filter on my system to keep the screen from clogging on the faucets and shower head. When flow is restricted, the "instant" ain't and it COLD.

I have been running this unit for a little over a year, so not enough time for reliability opinions.

 

[wawajake]

I have a tankless propane hotwater (in combo with my heating system boiler) I kept the electric hotwater tank as backup because I was too lazy to remove it just yet.
Be prepared for the cold water sandwich occurrances , mine is 13 seconds and occurs between every shower no matter how close you take one after the other because as soon as you shut off hot water it needs to rethink the whole safety purge system ,(electric does not have that happen).
Cost wise it will differ by location but for me two people in house I figured my electric hotwater tank cost me $40 a month and with propane at 2.60 a US gallon ( 68 cents a litre) it was costing me $40 bucks a month in propane.

 

[Gary Fowler]

I did have a tankless water heater in an apartment in Peru that worked ok but nothing was more than 20 feet from the heater which was outside. It worked on flashlight batteries for ignition and a portable propane tank for gas. One bottle (upright size that is about chest high, don't know the weight) would last wife and I for a month but we used cold water for washing clothes and only used hot water for dishes and bathing. Having used that is why I initially considered tankless for the house but after reviewing ALL the intricacies of ownership, I decided against it.
When considering the tankless systems when I built my new house, I decided that it was impractical to use an electric system as it took almost 200 amps just to run it and I didn't like the maintenance required to keep up the warranty which was going to cost me at least $100 per year for coil cleaning and other "required" maintenance items for the full warranty to be upheld (read the fine print of the tankless hot water heater warranty).
I instead opted for an electric tank model with recirculation pump to keep hot water to all faucets that are more than 20 feet from the water heater tank. I don't really know how much it cost to run but it is maintenance free and hot water is within seconds of the tap whenever I turn it on in any part of the house. Water waste is all but eliminated with the recirc pump. I sometimes wish I had propane available for heat, but with the recent surge in costs, glad I don't have to depend on $4 a gallon propane and also don't have to contend with gas leaks or deadly carbon monoxide build up from a gas fired appliance.

 

[kenmac]

Tankless water heaters aren't set it and for get it. They require a fair amount of maintenance . I don't care how much you filter your water, When water is heated all the minerals will separate out of the water and end up stopping up the water passages in the water coil ..If you perform the required maintenance you should be ok. Other than maintenance, there are a fair amount of electronics. When these parts fail it's expensive to repair. Tank type water heaters are more forgiving when it comes to maintenance .. They can be said to set them and forget them, & they have less parts to fail.... As a contractor, I can purchase and install any water heater I want... For me it's the tried and true tank type water heater NG, Propane or electric. Their pretty much maintenance free and if a part fails it won't wont cost you an arm and a leg...