Thinking about switching to a tankless water heater.?

I will need to replace my gas water heater soon, and am thinking about going with a tankless model.  Most people buy tankless due to high hot water usage, but I am considering it for the opposite reason.  I live alone and work 12 hour shifts.  That means that in a 2 week period there are 7 days where no one is home for 13 hours at a time, but I am still paying to keep the tank hot.  Tankless is much more expensive up front, so I'm trying to decide if I will make that up over time. 


Thanks for the info.  After I read your post I did some research on the extra maintenance  My house is on a well and has a lot of minerals.  I believe the little bit of extra gas I use will take years and years to make up the cost difference, and I don't need extra maintenance.   

13 Answers

  • elhigh
    Lv 7
    1 month ago
    Favorite Answer

    Tankless models come with certain, unskippable maintenance needs.  Frankly tank water heaters also have maintenance needs but the tank itself is pretty forgiving and many people skip the maintenance for years and never know there was something they were supposed to do.

    But tankless models will get bad fast if you skip the regular deliming process.  Mineral buildup is a THING with tankless models, and the higher your mineral content is in your local water, the more of a thing it will be.

    At my house when I replaced my last water heater, I included a timer that would turn it off during the day when I'm gone, and also at night.  It had an immediate, noticeable effect on my utility bill.  You could do as much.

    Another thing worth considering would be to add insulation to the tank.  This is especially true with gas water heaters; their tanks are not especially well insulated due to the affordability of the fuel and the fact that the flue running through the center takes up some of the volume; since it's so cheap to heat the water giving up some insulation gains back the tank capacity while keeping the tank a manageable size.  But you could add insulation to the tank, bearing in mind it needs to breathe to get air to the burner, and sharply reduce its losses during away times and reduce how much time is needed to return to the setpoints when the timer fires it back up again.

  • Anonymous
    4 weeks ago

    Yeah, but that is because the pilot light is still burning(on the older units) and it has a built in thermostat (a temperature sensor) to keep the water tank heat at 160 F degrees.Some people have the temperature at 180 -210 F(which is scalding hot.  Sometimes it is needed because water source is not "virus free" and the hot water nukes those bugs.  Others are on city water that is chlorinated and that bleach is a beach on those bugs not killed off by the boiling hot water. If you let your tank go cold. then it takes about 4 hours before that water in the tank is up to temperature.  That is a long time to wait to have a shower.

    I had gas and it got replaced on me.  I did ask about the tankless.  The tankless are instant heat (so they claim) and the tankless is put under the kitchen sink in the cabinet. However if the shower is not nearby then you got to wait for the water to heat up before you step into the water(I am not not into that ice water wash) so a second unit is installed near the shower.  OR you could put it where the gas tank stood and just wait.

    . The store clerk said they were being returned as fast as being bought.

    . So I bought an electric HW tank that was the size of the gas tank and put it in the same spot where the other stood.  The electric has the same heat sensor so the temperature does not drop more than 15F degrees before it turns on to keep it hot.  As I am on chlorinated city water, the temperature on the tank is on L(so maybe 165 F) because sometimes I come home drunk and scalding water is not something I want to wake up to in the shower.

    That is the way this stuff works.

    My gas HW tank was already 35 years old and no sign of leakage.  Freaked out the plumbers.(way more than the usual 10 years before failure)

    I have electrical experience to wire up an electric heater. I do not have a gas ticket to hook up a gas heater(I need a ticketed gas man to do the connection) Fire insurance rules.

    That is the info I got.  They are popular in Europe as houses are smaller there so having a big tank taking up floor space is a waste.

  • 1 month ago

    If you are paying more that $10.00 month to keep the water in the tank hot, your tank is poorly insulated. If you buy a new tank, it should be able to maintain temperature all day without using enough gas to notice.

    By the time you save enough to pay for the installation, you will be on your 2nd or third replacement.

  • 1 month ago

    a tankless heater will be better for you but if the existing gas pipes are not big enough they will have to be replaced . A tankless heater when on draws more gas .  A plumber can advise you of all this 

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  • 1 month ago

    Actually a tankless water heater is a good investment no matter how little or how much it's used. It creates your hot water on demand--which is always going to be cheaper for you. I'd say go with it. Yes, the install and equipment is more expensive, but it's the best way to use your resources. And yes, you'll make up the savings eventually. 

  • F
    Lv 6
    1 month ago

    I think you are describing what we call a combi boiler in the UK. 

    The advantages are unlimited hot water on demand including brilliant showers at near mains pressure. Also there’s no heat loss from a hot water tank.

    The disadvantage is everything works directly from the mains, so in a large household with multiple useage everything works at reduced flow.

    However for smaller households they work really well.

  • drip
    Lv 7
    1 month ago

    How long do you plan on living  where you are at?

    I wish I had one installed when we bought out house back in 1998. Now we are older and may not be in our house more than five years.

    How much is your water heater costing you to run.

    Consider buying an energy efficient water tank and insulation jacket. 

  • 1 month ago

    not worth it.  you'll have to install electrical as well ... too expensive unless doing it when the house is built, or you can DIY an appropriate circuit.  Consider switching to electric and putting the tank on a timer -- it only really needs to be hot about one hour a day for a single guy -- the hour during which you shower up and do the dishes.

  • Barry
    Lv 6
    1 month ago

    In the UK we call them combi boilers. But there is no doubt they are the most economical of the gas fired water heaters. You only pay for what you use as there is no standing heat loss.

  • Pearl
    Lv 7
    1 month ago

    thats up to you

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