Tank vs tankless water heaters

Any suggestions between the two?

Reply to
Kurt Ullman
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Is this a house being built or an older one ? If older, you will have to have heavy wiring or a gas line ran. Location may be a factor, If it is very cold in the area, many of the tankless may not heat the water hot enough for you.

Cost is usually much more for the tankless.

I would say stay with the tank.

Reply to
Ralph Mowery

Hi, When I was considering the tankless, the initial cost was VERY high. We have 4 bathrooms of which one has a Jacuzzi tub. Installing bigger gas feed line, preparing to mount the unit on the wall, correct unit sizing, etc. Felt like I was getting into possible headaches. Stayed with NG gas fired conventional top end model tanks. At least I could replace tanks twice and some for the cost of tankless install.

Reply to
Tony Hwang

If you use a lot of hot water I think the tankless will edge out the tanks. But you need to have the gas or electrical supply. Tankless use a lot of energy over a short period requiring big "pipes" to get it to them

Reply to
jamesgang

I'm sure there were, but I wasn't there to hear them talking.

I'm told it was something like this

Tankless: Hey, you need to lose some water weight.

Tank: Why would I listen to you? You have no substance.

. Christ> Any suggestions between the two?

>
Reply to
Stormin Mormon

If it were me, I would stick with the conventional tank style water heaters because they CAN supply all the hot water you need, whereas that's still a big question with tankless heaters.

In fact, in a house in the town I grew up in, the builder (who was a plumber by trade) put a ball valve in the basement separating the kitchen and one bathroom from the laundry room and the other bathroom. He installed two 60 gallon hot water tanks and had one to supply each side of the house. He did that because he had three daughters and they were always fighting over the one bathroom in their old house.

I thought that was actually a smart idea because the cost of a water heater isn't that much, AND the two water heaters don't have to be identical. They can be totally different and his system would still work fine. And, the best part of it is, if you ever have to shut one water heater down (to replace the annode rod, for example), then you can open that ball valve and have the heater that's still operational supply water to the whole house until the work is done.

If I were building a house, that's probably the route I'd go.

Reply to
nestork

I did hours of research on this subject a while back.

Learned tankless is overly complex, still has quirks/idiosyncrasies and is likely to generate expensive maintenance issues down the road. Additional gotcha's include the probable need to install a higher capacity gas line.

Plumbers hype tankless due to their greater initial purchase price, additional installation and future maintenance/repair income.

(Anyone remember ol' Rube!)

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Conventional tank type heaters may require a little more space/volume, but are cheaper, simple, reliable and have an extensive proven track record. In my book, they're right technology for the job.

Like someone said, do your homework... and if the conclusion is tankless; do it over again.

Don't just take my word for it, there's a lot on the internet.

Good luck!

Erik

Reply to
Erik

I personally don?t trust any manufacturer anymore to provide repair parts for anything they sell.

Reply to
recyclebinned

Compare them...

  1. Initial cost tankless - high tank - relatively low

2.Energy use tankless - high for short time, zero after (except for pilot for gas) tank - high when recovering, low and intermittent thereafter

  1. Volume of hot water tankless - unlimited & continuous up to rated capacity tank - limited

  1. Cost of operation Can't say for sure but I'm betting the tankless would be way less.

My only experience with tankless was when my wife & I lived on a sail boat for ten years. I put in a small LPG tankless so we had hot water for showers, washing dishes, etc. It worked very well for the entire time, never a problem. I wouldn't characterize it as "complex"; not much to it other than a gas valve.

Tankless seem to be more popular in non-US countries; there, it is not uncommon to only have hot water for the bathroom (none in kitchen, no clothes washers) and they are frequently installed in or near same.

The most attractive thing about tankless is their lower energy use; the least attractive, their high initial cost. The lower energy cost is especially attractive to me now that the LPG bandits are charging us close to $5.00/gal. for LPG; nevertheless, if I were putting in a new one, I'd probably go for a tank...a small 30 gallon one (only two of us) with the best insulation available.

Reply to
dadiOH

No reason it's a big question. You determine your maximum simultaneous demand, the lowest incoming water temp, and buy a tankless that is spec'd to deliver it. They all have that spec, it's not a mystery.

So, there is a similar sizing problem with the tank type.

The downside of course is that you have to replace two water heaters when they reach EOL.

Reply to
trader4

I don't see why it would be way less. From what I can see, the biggest energy savings difference comes from the fact that the tankless eliminates the standby losses coming from the tank type that has a hot tank of water slowing losing heat 24/7. However, I have a gas water heater and in the summer, no other gas usage other than some for limited use of the outside gas grill. In summer, my gas bill is about $16 a month. So that includes heating the water I actually use, a little gas grilling, and whatever the standby losses are. Which means the standy losses can't amount to very much. If it's $5 a month, it would take a very long time to recover the higher initial cost of a tankless. Also, the gas water heater I have is just a basic model with a pilot light. For a couple hundred more you can get a power vent, higher efficiency one, that would reduce the standby and operating losses.

So, I'm not convinced the tankless are going to save enough on energy to make them cost effective.

One other factor to add to the usual list of differences is that with a tank type if you lose power, you still have a tank of hot water that can last a couple days of limited use. If you have a gas tankless, some of them will operate without power, some will not.

Reply to
trader4

??

I have a conventional tank, not power vented, and if I lose power I still have an unlimited amount of hot water available to me.

Now if they can figure out how to make a natural-gas-powered furnace fan motor, then we'd have furnaces that would keep our homes warm in the winter during power outages (those of us that have 30+ year-old furnaces that require almost no electricity to operate beyond the fan that is...)

For tankless, nobody here mentions incoming water temperature and the difficulty that tankless has in northern climates in the winter.

The OP (Kurt Ullman) appears to be located in Indianapolis - so it's not clear to me how he would be affected by incoming water temperature:

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Another aspect (that I've just discovered after doing some goog'ling) is that it seems to be common for tankless heaters to have flow restrictors on their output (designed to promote more residency-time for the water inside the unit to be heated) but this has the effect of causing lower water pressure in the hot-water lines running from the unit to the rest of the house when hot water is being used anywhere and thus a mixing imbalance at fixtures like sinks and showers.

Reply to
Home Guy

Maybe, but there's little difference in economy.

The lifespan of a water heater's tank is largely determined by the amount of thermal shocking it endures, and that's directly related to the sizing of the tank. The larger the tank, the smaller the drop in temperature in the tank when hot water goes out and cold water comes in, so the smaller the thermal shock each time hot water is used. So, by using a 60 gallon tank for one bathroom instead of two, you SHOULD expect to get a much longer lifespan of the tank in that heater. I don't know if it would be double, but it would be much longer than using that one tank for both bathrooms.

So, it's a pretty good overall gameplan in my books.

Reply to
nestork

What everyone seems to miss, is that there are three types of tank gas water heaters. 1 - Conventional vented water heater, cheap with little efficiency.

2 - Power vented water heater, mid-priced, needs no chimney, little gain in efficiency. 3 - Condensing water heater, highest price, needs no chimney, very high efficiency.

I have a condensing water heater, it can heat an ice cold tank in 10 minutes, you cannot use the water faster than it can make it, it just sips gas and dropped my gas bill by $20.00 per month over my old conventional heater.

Reply to
EXT

Interesting theory, but I suspect it's not true. I don't accept the idea that thermal shock is the dominant failure mechanism.

I

If you have any real data that says the above is true, I'm sure we'd all like to see it.

Reply to
trader4

Virtually all the condensing water heaters are tankless, no? I just googled and looks like Rheem announced they were making the world's first tank type condensing unit. And it brags about an energy factor of .80 I'm still betting that it takes one hell of a long time to recover the cost difference.

A cheapo regular tank type GE water heater that costs $347 at HD has an energy factor of .59 and an estimated annual operating cost of $309. Looking at the GE power vent model, it cost $845, has an EF of .67 and costs an estimated $272 a year to operate. So, it would take 14 years to recover the extra money it costs for the more energy efficient one. And that ignores the time value of money, the fact that it may not last

14 years, etc. Everytime I look at water heaters I come to the same conclusion. The higher efficiency, much higher priced units, don't have an economic advantage. At least not in my world. Apparently not in the EPA's world either, because those energy factor numbers and costs to operate are their numbers.
Reply to
trader4

I got estimates from at least 3 reputable licensed plumbers for both. Estimates for a tank-type were pretty consistent. Estimates for tankless were all over the place, so that alone convinced me to stick with something that everyone knows how to install.

Even with moving it from inside the house to the garage and installing a new roof vent, the total cost was 1/3 that of a whole-house tankless type. And it just plugs into a standard 110 receptacle. Installation was simple and easy to check. Energy rebates for both types had little effect on any of the systems we were looking at.

One plus for whole-house tankless would be it can be mounted on an outside wall and free up room inside if that's important. But then you have all the exterior wall penetrations.

Whole-house tankless would also have required extending gas piping and new 220V wiring. I'm not a big fan of running 220V when there is an alternative. Plus this house has a 50 year old breaker box & wiring which would have required upgrading.

Tank type here is gas, which is a lot cheaper to use than electric around here.

Reply to
Guv Bob
7PnZ2dnUVZ snipped-for-privacy@earthlink.com...

timates for a tank-type were pretty consistent. Estimates for tankless we re all over the place, so that alone convinced me to stick with something t hat everyone knows how to install.

new roof vent, the total cost was 1/3 that of a whole-house tankless type. And it just plugs into a standard 110 receptacle. Installation was simple and easy to check. Energy rebates for both types had little effect on any of the systems we were looking at.

e wall and free up room inside if that's important. But then you have all the exterior wall penetrations.

w 220V wiring. I'm not a big fan of running 220V when there is an alternat ive. Plus this house has a 50 year old breaker box & wiring which would ha ve required upgrading.

I don't see why a gas tankless would need 220V. Nothing there that should require 220. What does it have? Some electronics, an ignitor, maybe a draft inducer blower?

But the rest of your experience is consistent with what we've heard here before. I think for the right application, tankless can make sense, but it usually doesn't make sense for a replacement of an existing gas tank unit. And if it's going into new construction, that can greatly reduce the cost of the install.

Reply to
trader4

Electric controlled natural gas tankless won't work during power cuts. When ice storm 2003 hit, I was out of power, four days. A hot shower (old style tanked natural gas WH) sure made life more comfortable.

. Christ>>

Reply to
Stormin Mormon

during power outages here people have run a garden hose thru the home with a slow flow of hot water to provide enough warmth to prevent freezing.....

tankless are just a bad idea all around. espically if you have teenagers, they can get a endless hot shower that runs up all the utility bills..

endless use of gas to heat the water, water and sewage, and even electric to run the tankless... bigger bills all around

Reply to
bob haller

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