In loving memory of Kenis D. Keathley 6/4/81 - 3/27/22 Loving father, husband, brother, friend and firewood hoarder Rest in peace, Dexterday

Hot Water Heater

Discussion in 'The DIY Room' started by ReelFaster, Feb 9, 2026.

  1. golf66

    golf66

    Joined:
    Jan 22, 2014
    Messages:
    436
    Likes Received:
    1,862
    A gas tankless water heater merits consideration. They can provide limitless hot water when properly sized. There is the benefit of only using gas when there is a call for hot water and not burning gas 24-7 to keep tanked water hot. Add in the space that is gained by removing the tank. Rinnai makes some excellent units. I have a tankless electric and love it. It was a bit of a witch to set up because it required 6/3 wire from the main panel to a subpanel along with a 100 amp breaker. Your current setup can be easily switched over to tankless with out the hassle that I went through.
     
    Horkn, John D, bogieb and 3 others like this.
  2. TurboDiesel

    TurboDiesel

    Joined:
    Nov 22, 2013
    Messages:
    16,226
    Likes Received:
    97,470
    Location:
    Hollidaysburg Pa
    Julie has put in about 70 AO Smith on-demand gas water heaters. they are lasting 2-4 years depending on location. Some have only lasted 1 year and Smith was supposed to warranty 5, but somehow the rep didn't see it through. Of course, these are all in the restaurants and are VERY high usage.
    Personally, I love our electric tankless at home. (EcoSmart 27) its been in about 12 years with no problems after the first couple months.
     
    Horkn, eatonpcat, golf66 and 2 others like this.
  3. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    24,645
    Likes Received:
    159,778
    Location:
    NE Ohio
    Well, that lines up with what I've heard from other reputable plumbers...they generally don't recommend them to people they like... especially in areas with hard water.
    One of the bosses had a small electric on demand heater put in at work... we'll see how that does...but it'll see very little use, so it may be fine.
     
  4. Canadian border VT

    Canadian border VT

    Joined:
    Feb 18, 2015
    Messages:
    19,270
    Likes Received:
    127,812
    Location:
    Vermont
    My plumber agrees with TurboDiesel and brenndatomu hard to save $ with efficiency if need constant replacement or repair especially with wells read harder water normally
     
    Horkn, gusty60, eatonpcat and 2 others like this.
  5. Erik B

    Erik B

    Joined:
    May 12, 2015
    Messages:
    5,594
    Likes Received:
    38,634
    Location:
    Western Wisconsin
    Do you need more than 1 tankless heater if there are15-25 feet between points of use?
     
    Horkn, eatonpcat and bogieb like this.
  6. bogieb

    bogieb

    Joined:
    Mar 30, 2015
    Messages:
    12,481
    Likes Received:
    75,857
    Location:
    New Hampshire
    My propane combi boiler, which has on demand hot water is an HTP. It is advertised (at least in early 2023, when it was put in), as a "lifetime" warranty. If you register it within 30 days, it has a 15 year (limited) warranty. Otherwise it is 5 years. I found that isn't unusual that "lifetime" pretty much describes what they have determined it means, not the customer's lifetime.

    You really have to read the documentation to see that you need to register it for the longer warranty. Fortunately, I was looking for how to register it when I found that little gem, so was able to take advantage.
     
  7. golf66

    golf66

    Joined:
    Jan 22, 2014
    Messages:
    436
    Likes Received:
    1,862
    My EcoSmart 27 electric tankless is 13 years old and performs like new. Of course, I just forked myself and it will probably break down today ;-) Installation was a witch because due to a code issue, I had to run 6/3 wire from the main panel and install a subpanel in the laundry room. Prior to the electric tankless I had a 50-gallon electric tank. My electric bill dropped by $50.00 per month after installing the tankless.
     
  8. eatonpcat

    eatonpcat

    Joined:
    Oct 5, 2013
    Messages:
    10,118
    Likes Received:
    57,350
    Location:
    Eaton Township, OH
    Who knew that you had running water?
     
    Horkn, bogieb and brenndatomu like this.
  9. ReelFaster

    ReelFaster

    Joined:
    Dec 1, 2016
    Messages:
    2,857
    Likes Received:
    19,785
    Location:
    S.Jersey
    If I can buy the same hot water heater I have now I'd buy it all over again. 20yrs ain't too shabby!
     
    gusty60, Horkn, bogieb and 1 other person like this.
  10. brenndatomu

    brenndatomu

    Joined:
    May 29, 2015
    Messages:
    24,645
    Likes Received:
    159,778
    Location:
    NE Ohio
    I'd bet you can't...they change model #'s every 6 months on appliances now. They find ways to cheapen them up, bit by bit...drip, drip, drip. (no pun originally intended there :D)
    It might be the same series, but if you compare the model number, they change 'em up...heck, on some stuff its hard to get the exact same model # from 2 different vendors even!
     
    gusty60, Horkn, bogieb and 3 others like this.
  11. ReelFaster

    ReelFaster

    Joined:
    Dec 1, 2016
    Messages:
    2,857
    Likes Received:
    19,785
    Location:
    S.Jersey
    I am sure I can't for sure.................the ole "They don't make em like they use too"
     
  12. chris

    chris

    Joined:
    Oct 9, 2013
    Messages:
    3,166
    Likes Received:
    11,272
    Location:
    SE WI
    my water heater on lp and well is from 1991- still going, don't remember name - dosen't matter as everything now is made to last just over warranty. Repair parts are insanely priced+ instalation if not done yourself generally adds up as much as new or pretty dang close. I was recently quoted 2 grand for a 50ft run of 8ga,200v single phase line. Nutz.
     
  13. Farmchuck

    Farmchuck

    Joined:
    Dec 18, 2016
    Messages:
    1,788
    Likes Received:
    8,782
    Location:
    Nepa
    If you’re considering electric a Marathon water heater is a unit we’ve had good luck with. They are a bit pricey but they last. The one in our milk house lasted 22 year's if I remember correctly. We also have one in our house & my wife’s parents house. Just something to consider.
     
  14. Horkn

    Horkn

    Joined:
    Dec 17, 2014
    Messages:
    29,087
    Likes Received:
    165,829
    Location:
    SE Wisconsin
    Yep. It's just a water heater. It's a funny thing that many people just say.

    Water heaters vary crazy amounts of service life depending on the water that's being supplied. I used to work for my dad's plumbing and boiler company about 90 miles from where I live. That city where the business was had such hard water, city it country, that the nutrients in the water would build up in very short time. Water heaters they're would last a couple years at most. Electric or gas didn't matter. 5 years was about max. Not sure about on demand heaters because they were just coming out when he got out of that biz.
     
    Last edited: Mar 6, 2026
    bogieb, eatonpcat and brenndatomu like this.
  15. eatonpcat

    eatonpcat

    Joined:
    Oct 5, 2013
    Messages:
    10,118
    Likes Received:
    57,350
    Location:
    Eaton Township, OH
    We are on our second Rheem Marathon Electric water heater bought and installed by our Electric Coop LMRE. The first one lasted 20+ years and our Co-Op honored the lifetime warranty and installed a new 80 gallon tank for free. Labor and the new unit, plus took the old one away for a zero dollar invoice
     
  16. don2222

    don2222

    Joined:
    Nov 10, 2013
    Messages:
    3,422
    Likes Received:
    4,826
    Location:
    Salem NH
    I have a 40 gal SuperStor tank on a separate zone on the Buderus boiler with Tekmar control. It works well but they all die after a while so I just picked up an ECO Smart On Demand electric DHW panel from Home Depot for backup. :)
    By adding a cross over pipe and a ball valve I can switch in what ever DHW heater I want.
    Since I have a pellet stove running nearby to heat the house, when I switch to the electric on demand, I can still switch in the 40 gallon tank which gets heated by the pellet stove to 80 degrees by Osmosis, then the EcoSmart heats that from 80 to 140 degrees for greater efficiency. :)
    Pic 1 - ECO Smart on demand
    Pic 2 - Buderus Bouler
    Pic 3 - 40 Gallon SuperStor
     

    Attached Files:

    Last edited: Mar 15, 2026
    Horkn and brenndatomu like this.
  17. morningwood

    morningwood

    Joined:
    Oct 17, 2022
    Messages:
    418
    Likes Received:
    1,987
    Location:
    Ohio
    Zwave control of water recirculation pump : r/homeautomation

    Get a ZWave (preferred over Chinese Wi-Fi receptacles) outlet, and a motion sensor. Person walks into the room; the motion sensor has an automation that turns on the ZWave outlet the pump is plugged into. The outlet turns on and runs the pump for X minutes / seconds.

    Have something very similar for the light in my daughter's bathroom. She walks in, the light turns on via motion sensor automation. She walks out, a minute later the light turns off. Probably spent more $$$ on the outlet, and the sensor than what I would have spent on electricity, but I hate lights on in an unoccupied room (pet peeve).
     
    Last edited: Mar 18, 2026
  18. billb3

    billb3

    Joined:
    Oct 7, 2013
    Messages:
    10,470
    Likes Received:
    54,278
    Location:
    SE Mass
    Depending on utility prices in your area, several studies indicate if you use more than 40 gallons of water a day you may be better off with the good old water tank than on-demand. And the converse is true - if you use less than 40 gallons a day you'll likely spend less in the long run with an on-demand system.
    Don't forget: if you live in an area where deposits build up in a tank, they'll also build up in your on-demand often requiring yearly maintenance. Labor rates are not going down.
     
    Horkn, gusty60, Farmchuck and 3 others like this.
  19. don2222

    don2222

    Joined:
    Nov 10, 2013
    Messages:
    3,422
    Likes Received:
    4,826
    Location:
    Salem NH
    Hello
    I like the OnDemand DHW panels. Saves space and easy DYI repairs to save $$$ !!!
    I have the electric ECO smart from Home Depot that I installed with a friend going on 10 years and just got very familiar with the 2nd of the only 2 most common issues you can have and easily replace yourself with a screw driver and a socket wrench. The first issue after 6 years just a Phillips screwdriver was needed. The only maintenance needed is flushing the electric heating elements. If you size it right you have all the hot water you need and no energy loss when you are done. Just my 2 cents.

    1. Flow Sensor Replacement
    Electric Eco Smart On Demand DHW panel first Fix when element cleaning does not solve the problem
    2. Heating Element replacement
    EcoSmart 27 OnDemand Electric DHW panel heating element replacement - Copper or Titanium?
    3. Maintenance Cleaning with flush valve kit
    Electric Eco Smart 27 KW On Demand DHW Isolation Valve install for easy heating element cleanings?

    Turbodiesel has his for over 12 years and really likes it.
    Golf66 has his for over 13 years and saved $50 per month on his electric bill since switching over from his $50 gallon electric DHW tank. See their comments in this thread below.
    Hot Water Heater
     
    Last edited: Jun 15, 2026 at 11:15 AM
    brenndatomu likes this.