Is there a reason to replace a working water heater with a new tankless water heater?

Asked by Lynn Anderson, San Francisco, CA Tue May 29, 2012

Other than the tankless water heaters being more efficient, are there more reasons why tankless is better? The older water heater still works fine.

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Robert Ernst’s answer
Robert Ernst, Other Pro, Reno, NV
Wed Jul 18, 2012
The tanklless water heaters can often save money by not keeping a whole tank full of water hot all day. The best way to be Green would be to leave what you have there until it needs to be replaced. As long as your current water heater is working fine removing it and getting rid of it is a waste. Water heating on average is about 15% of your utility.

Some things to think about when changing to tankless are if there are long runs of piping since this is where your going to leave the water you just paid to heat to cool off. A place that has cold water temperature in the winter has to heat the water a higher amount and so this might require a higher BTU tankless thus using more energy. Often the tankless needs more gas and a larger flue pipe. Also the plumbing needs to be reconfigured and possible even an electrical outlet installed. All this could add allot to the expense and lower your return on investment.
3 votes
Exactly. Don't replace a working water tank just to get the latest model. When yours goes out, then you might want to consider other options. But for right now there's no need to spend the extra money. If you're trying to sell, then you should spend that money on something that will raise your home value more. |
Flag Tue Feb 3, 2015
sfdragonboy, Home Owner, San Francisco, CA
Wed Jun 6, 2012
I am a SF home owner and I installed a tankless water heater when I did my remodel before moving in. It has been over 7 years since and it is great for my wife and I who are gone all day and we needed the extra space that was saved from not having a water tank. The bad thing is that my wife spends too much time in the shower, now that the hot water is endless! :-) What we did was install a circulating water line with a remote control so that when you wake up you simply hit the remote and the initial cold water is recirculated back into the system until nice hot water is flowing through. No wasting of water. Easy to get used to too.

While I would not change your water heater just yet since it is fine and working, something to keep in mind is how your venting situation would change if you went tankless. Keep in mind that because of the extreme heat that comes out of these special double walled vent piping is required or you need to mount the tankless unit outside so that it vents directly outside. If you can't do the exterior install, the cost of changing the vent pipes inside your home to outside may make it too expensive of an endeavor.
2 votes
It really is nice to have endless hot water! Since I live in a house with five other people, we really need this feature. My family only had one bathroom a few years ago, and the hot water always ran out. I hated being the last one to take a shower, for that very reason! Tank-less water heaters really are the way to go.
Flag Fri Jan 16, 2015
I'm not sure if I would replace it if it is still in working condition. You know what they say, "If it's not broken, don't fix it." Trying to replace something that is still in great condition could end up just being more trouble for you in the long run!
Flag Fri Dec 12, 2014
Oggi Kashi, Agent, San Francisco, CA
Wed May 30, 2012
If you are remodeling your home then it's something to consider. It takes less space, hot water on demand, more efficient however, if it's electric, you'll have zero hot water at times the power is out. The tank usually allows for one or two showers with no power.

Your current water heater is working however, how old is it and what's its recommended operational life?

Oggi Kashi
Broker Associate, Paragon Real Estate Group CA DRE 01844627
All data from sources deemed reliable but subject to errors and omissions, and not warranted.
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2 votes
Eric H. Wong , Agent, Albany, CA
Tue May 29, 2012
Tankless is not always the best and most efficient choice. If you want to be more green, but you also want to save some money, you might look into the newest generation of super-insulated water heaters. They retain 90+% of the heat, and they give tankless water heaters a real run for the money. When you add in the fact that they can be a few thousand dollars cheaper to install, the newst tank water heaters are worth a look.

Good luck
2 votes
lewisremingt…, Home Owner, Rochester, NY
Mon Apr 6, 2015
I think if your old water heater works just fine, then it might not be necessary to replace it. You could always calculate the savings you would have if you switched, and see if the cost of switching would be outweighed by it. But I think you could just wait till your current water heater breaks to replace it.
1 vote
karablader, Home Buyer, Utah County, UT
Mon Jun 16, 2014
I would say that if your current water heater is still working fine, why replace it? You might as well get your full moneys worth out of it before giving it up. Once that one goes out, then yeah, it would be a great option to switch to a tankless water heater.
1 vote
Kara, I agree that you shouldn't replace your water heater if it is functioning properly. Unless you have a really old water heater that is inefficient it doesn't seem worth the replacement cost. I would wait until the water heater needs to be replaced before making the switch to a tankless system.
Flag Sat Jan 24, 2015
John Arendsen, Agent, Leucadia, CA
Thu Apr 10, 2014
Boy I would think by know Lynn would have made a prudent choice as to what she intends to do about her water heater. This question is almost 2 years old. Do you think she's really looking back on this question?
1 vote
Bill Eckler, Agent, Venice, FL
Thu Jun 7, 2012

With a standard water heating system, you always run the risk of running low on hot water especially when drawing from multiple sources such as washer, shower, and dishwasher being used at the same time. With a tankless system, this does not happen. A tankless system will also create additional floor space.

Hope this helps,

1 vote
I think the newer water heaters are more efficient, but other than that I don't think there is really a difference between your two choices. I would wait to get a new water heater until the one you have right now breaks down.
Flag Tue Dec 9, 2014
Matthew Goul…, Agent, San Francisco, CA
Wed May 30, 2012
Hi Lynn,

I agree with others, if it works dont fix it unless you are remodelling and it makes sencse to regain the space.

I also agree with Mike about the water reserve in the case of an earthquake. Not only did this aid some friends who were here in the last quake but ti was a savior for a good friend in NZ the other year when the second large quake hit his home near Christchurch.

If you go tankless make sure you have extra water in your emergency kit just in case.

1 vote
Ron Thomas, Agent, Fresno, CA
Wed May 30, 2012
Water Heaters rot from the inside-out: You may not see any problems, but they may be out of sight:
How old is your water heater?
If it is 7-8 years old, (or def older), you should replace it:
You will see minerals in your water, and maybe the taste has changed.
You could have a water tech come out and test your water, but why?

Now, if you are going to change it; I would recommend the tankless, for all the reasons.
And that bit about having water if there is an earthquake is laughable; why not build your concrete bunker too? If you are that paranoid, you shouldn't be living in S.F.

Good luck and may God bless
1 vote
Mike Ackerman…, Agent, San Francisco, CA
Wed May 30, 2012

Keep the old water heater... I'm an old geezer (55) who grew up in the SF Bay Area. In the event of an earthquake - you will have a source of 40 - 50 gallons of drinkable water that a tankless will never have.

If it's for space reasons or energy efficiency - so be it - but my two water heaters (two units) are my insurance to clean clear drinkable water in case the Hetch Hetchy busts for a couple days.

Back to the old saying 'If it ain't broke, why fix it.'

All our best,

Mike Ackerman
Zephyr Real Estate - We're all about San Francisco!
1 vote
John Arendsen, Agent, Leucadia, CA
Tue May 29, 2012
Lynn, if it works don' fix it. There's a whole new installation and hook up dynamic that must be introduced into the mix whence you integrate a tankless system into your traditional water heater. I have a tankless and there are some other expenses you will need to address.

If you're not having any problems with your traditional water heater keep it until you do and then go tankless. Additionally, I can't tell you how many times I've been standing in my shower under hot and cold running water with my new tankless. That's my 3 cents worth (adjusted for inflation).
1 vote
Lee Clancy, Both Buyer And Seller, San Francisco, CA
Tue May 29, 2012
You ideally never run out of hot water with a tankless heater, so that's a big plus right away. For whatever reason, tankless is more expensive in the US vs. other markets like Europe where they're super common, so that's another consideration, but in the long-term my guess is that the US will end up primarily tankless in a decade or two.
1 vote
Kelsey Compa…, Home Buyer, Provo, UT
Tue Apr 14, 2015
There could be a number of different reasons for a replacement like that. Even if it is working it may be time for an update. I know my parents just had their really old water heater replaced.
0 votes
Jackson Will…, Home Buyer, Provo, UT
Wed Apr 8, 2015
Unless you're going to save a significant amount of money by switching to make it worth buying and installing a new unit, I'd wait for a while. It's definitely difficult to figure out things like this to say the least. If you're struggling to figure out how much this could help you, you should talk to a professional. If you get the right amount of help from a professional, you'll be better able to figure out what you need, and what your best options are.
0 votes
mattdalek47, , Columbus, OH
Fri Nov 7, 2014
That is something best discussed with a professional in this area. A tankless heater can be a nice switch that can last longer and possibly fill your needs better. But only you can decide that with the help of a specialist.
0 votes
Arpad Racz, Agent, San Jose, CA
Thu Nov 6, 2014
Hi Lynn,

Depending on how old the current hot water heater is, many people would try to get a useful life out of this one first.

Kind regards,

0 votes
garypuntman, , Los Angeles, CA
Thu Nov 6, 2014
If you want an update, then it might be a good idea. I have also heard that they are energy efficient. I have been thinking about getting a new water heater myself. I think it sounds like a good reason to get a new one.
0 votes
Raydah Abdel…, Agent, San francisco, CA
Wed Nov 5, 2014
My husband and I recently remodeled one of our units and replaced the water heater with a tankless water heater. It will take some time to see the advantages. But it is well worth changing it right now. The old heater is probably taking longer to work even thought it is working.
0 votes
trippvanderb…, , 10027
Mon Nov 3, 2014
If your water heater works then I don't see why you would replace it. I would wait until it breaks or has problems to buy a new one. If you see the need to buy a new one then do it.!heating/c1jo3
0 votes
My NC Homes…, Agent, Chapel Hill, NC
Tue Jul 22, 2014
If it's still working fine my own advice is to wait till it needs to be replaced before doing it. One advantage of tankless water heaters beside their efficiency is that it supplies unlimited hot water unlike traditional water heaters which are limited by their size. For large families this can be either a real benefit (or simply supply the household shower hog a reason to stay in even longer.)
0 votes
Bill Eckler, Agent, Venice, FL
Tue Jul 22, 2014
Yes, tankless water heaters are more energy efficient and less expensive to operate because you are only heating the water that you are using. As far as should it be replaced? I'm from the old school and believe...."if it ain't broke don't fix it!"

0 votes
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