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Community and Q&A

Hot Water Heater

clarkfamilyct | Posted in General Questions on

We’re in need of a new hot water heater because our current one has failed. What type of hot water heater is best? A stone heater has been recommended to us as an option. Is this an ideal option? Thank you!

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  1. GBA Editor
  2. Expert Member
    Dana Dorsett | | #2

    The answer depends on your hot water needs, the available fuel sources, and the budget, and any other goals.

    To home on it a bit, perhaps you can share:

    Where are you located...

    ... how many bathrooms... many people live there...

    ...what's the volume of the biggest tub you have to fill...

    ...what are your fuel options (and the local pricing)...

    ...are you looking at only lowest operating cost...

    ...would you pay more for something that lasted longer... you heat the house with hydronic system (pumped hot water)...

    ... is lower carbon footprint important to you?

    What means "...stone heater..." in your dialect?

  3. clarkfamilyct | | #3

    Thank you, Donna.

    Located in Connecticut
    2.5 bathrooms
    2 adults + 2 little ones (infant and toddler)
    we have a Jacuzzi but generally use only a shower, but we do have a lot of laundry (cloth diapers, etc.)
    We'll pay more for something that lasts longer and is the safest and healthiest option. For example, I've read that an aluminum anode should be avoided because aluminum can get into the water?
    The water heater company referred to an option as a "stone heater"

    Thank you!

  4. clarkfamilyct | | #4

    Also, in case it's helpful, the current water heater that needs this
    immediate replacing is 18-19 years old: Triangle Tube Phase III Model # TR-75, 75 gallon

  5. GBA Editor
    Martin Holladay | | #5

    "Stone heater" is probably shorthand for "stone-lined heater," which is marketing jargon for a tank made of enameled steel.

  6. clarkfamilyct | | #6

    Thanks, Martin. Would this be a good option? The company said that it doesn't need an anode and therefore is better? Any concerns about aluminum, lead, etc getting into the water supply?

  7. Expert Member
    Dana Dorsett | | #7

    How big's the Jacuzzi?

    Is it an oil fired boiler, or is it a hot air furnace?

    If boiler, how many heating zones, and what is the nameplate DOE output rating of the boiler?

    Is there a full basement, with the showers on upper floors, with good access to the drain stack in the basement?

    Describe the water heater that failed (type, size), and was it providing sufficient hot water?

    I've never heard of the term "stone heater" in a water heating context.

  8. clarkfamilyct | | #8

    The Jacuzzi is fairly large (larger than a typical bath tub)

    It's an oil fired boiler, and we have forced hot air heating.

    I believe that there are 3 heating zones downstairs and two upstairs (5 thermostats total)

    There is not a full basement.

    There is one shower downstairs that is never used, plus one shower upstairs. There is also a standard bath tub upstairs.

    Failed water heater: Triangle Tube Phase III Model # TR-75, 75 gallon
    It was working well until it failed.

    I'm not sure about the nameplace DOE output rating of the boiler.

    Thank you!

  9. GBA Editor
    Martin Holladay | | #9

    Many, perhaps all, of the Triangle Tube water heaters have stainless-steel tanks. If that's the kind of water heater you have now, then switching to enameled steel is definitely a step downwards to a lower level of quality.

  10. clarkfamilyct | | #10

    Great to know, Martin. Thank you. It sounds like a stainless steel tank + magnesium anode is the safest option in terms of drinking water? (infants and toddlers drink the warm water, etc.)

  11. Expert Member
    Dana Dorsett | | #11

    A bit of cross-posting going on here...

    The Triangle Tube Phase III is an indirect-fired water heater operating off the boiler. The 75 gallon capacity is probably in order to be able to fill the Jacuzzi. You could probably fill the Jacuzzi with an 80 gallon heat pump water heater, and keep the boiler out of the loop.

    Still need to know the DOE output of the boiler, and the number of zones.

    If the place is micro-zoned and/or the boiler is ridiculously oversized for any single zone, you may be able to improve net efficiency considerably with a "reverse indirect" operating as a buffer tank for the heating system , and as a hot water heater. With a reverse indirect the potable water is always inside copper tubing coils, which is suspended inside a tank full of heating system water. Whenever a hot water tap is opened, the water in those coils flows, with cold water entering the bottom, hot water leaving at the top. The total water volume in the coils is a couple of quarts max, but the water is heated instantly as it moves up the coils due to the high surface area between them.

    There are no anodes to worry about, and reverse-indirects typically have lifetime warranties in residential applications, but they're more expensive than a standard indirect, and there would be some design work, some heating system plumbing re-work and likely an additional pump added to the heating system. It won't be cheap, but it would probably get you there, depending on just how much burner capacity you have behind the thing.

    Here's on vendors' lineup :

    Here's another:

    Here's yet another:

    Since you're primarily a showering family, there's probably going to be real payback in a gravity-film type drainwater heat exchanger, especially when heating hot water with oil:

    There used to be distribution for one of the vendors through EFI in MA, but it looks like now you'd have to order direct from the manufacturer, or PowerPipe online via the Home Depot. Natural Resources Canada maintains 3rd party tested apples-to-apples efficiency numbers on different models and vendors to compare, but a typical 3" x 60" tall or 4" x 48" tall heat exchanger will come in at about 50-55% energy recovered under standard test conditions. One of the standard conditions is 2.5 gpm flow, which is on the very high side for most shower heads, and recovery efficiency is higher at lower flow. The fattest and tallest one that fits is the "right" one, since the labor cost of installation is about the same independent of size, and the increased return efficiency of wider & taller improves the payback period despite the marginally higher initial cost. At ~50% heat recovery you'd be using only half as much heating oil per shower, and for primarily showering families about half the total hot water is used in the shower. It won't save a drop for tub-fills though, since it only works when both the drain and the hot water are flowing.

    See also:

  12. GBA Editor
    Martin Holladay | | #12

    You wrote that you have "an oil fired boiler, and we have forced hot air heating."

    That's confusing. It's rare for a house to have a boiler unless the boiler is used for space heating. Do you have a hydro-air system -- a system with a boiler that produces hot water, connected to forced-air ductwork?

  13. user-2890856 | | #13

    Would be willing to guess it's a Burnham Alliance Dana .

  14. Expert Member
    Dana Dorsett | | #14

    Ah, the HydraStone indirect. Got it!

    Five heating zones, including a hydro-air zone, sounds like it's probably an oversized boiler that could benefit from buffering, but a better description of the heat emitters on each zone would be useful. It could be five air handlers, a single air handler with auto louvered duct zoning, or maybe there some baseboard or other type of heat emitters in the mix. It makes a difference.

    Your typical annual total oil use is...??? (or better yet a "K-factor on a mid to late winter oil fill-up slip).

  15. clarkfamilyct | | #15

    Thank you, all. The water heater company has offered two options. Will appreciate your thoughts on which is the best in terms of water quality. Thank you!

    Triangle Tube stainless steel indirect: Triangle Smart

    or Alliance AL-70 stone lined tank (no anode rods or metal contact)

  16. charlie_sullivan | | #16

    If we are just down to those two options and we are only considering water quality, that's a much narrower question than most of the answers you've gotten.

    Stainless is about as safe as it gets. If you cook acidic foods in stainless pots you get trace amounts of Ni and Cr in the food, but from plain water I think the amounts are negligible even if you are being super-cautious, and it's certainly safe measured against any established limit for that kind of thing.

    The HydraStone lining isn't just another name for porcelain--it's actually a cement lining. It's thick and porous. The water seeps into it, but gets depleted of oxygen quickly so corrosion of the tank does not progress. Cement is a complex material made from lots of different source materials, which can contain toxins. For that reason, cement linings for potable water systems are made from more carefully controlled mixes that have undergone testing to be sure they don't have toxins at levels exceeding regulatory limits. So that should be safe too, but you are are relying on the testing being done properly and counting on the limits for various toxins having been set at levels you are comfortable with.

    So I would tend to think that there are fewer unknowns with the stainless tank, and I would recommend that between those two options, as a better way to be sure you have good water quality.

    If you are willing to consider pushing your water heater company to consider other options, or you are willing to consider a different company, there might multiple advantages you could get, many of which have been discussed above.

  17. clarkfamilyct | | #17

    Thank you, Charlie, for your helpful reply. We're currently without hot water, so looking for the fastest possible water heater replacement, which will be the Triangle Tube tomorrow!

  18. user-2890856 | | #18

    Beware the Triangle tube and average plumbers . Down the road somewhere i it's life someone may want to service your TT indirect . I believe all they offer are tank in tank units , this is where the potential problem will rear it's head . A plumber that is not on the absolute top of his game may attempt to drain the DHW tank which is the inner tank , if and when this is done , that tank will collapse under the pressure the outer tank and lack of same on the inner tank . Proceed with caution . You could use the most widely used indirect that there is , SuperStor Ultra , stainless with coil , largest surface area exchanger available on similarly sized tanks .

  19. charlie_sullivan | | #19

    Thanks for the interesting warning, Richard!

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