Is Tankless really better??

Old 10-19-07, 11:30 PM
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Post Is Tankless really better??


I have a 6yr old 40 gallon gas water heater, which is starting to leak and I want to know whether I should just replace it or go to a tankless system. I realize that I will probably spend 2X in getting a tankless system, but is it worth it?? Would I recoupe the difference in a couple of yrs in the energy savings?? My wife and I are the only ones living in the house now, but we plan on having kids in 3-4 yrs. Can anyone shed some light that has a tankless system or is familiar?


Old 10-20-07, 11:06 AM
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i love tankless heaters. i sell them and have had one in my house for the last 2 years. i preffer rinnai heaters but there are many out there. around here, the price differece between a 40 gallon change out and a tankless install is aroud 3 time the price, not double. you won't recoup your costs just in energy savings in just a few years but if you consider that by the time the tankless needs to be replaced (20 years or so), you'll probably have gone through 3 regular heaters. by then, you'll be way ahead of the game. especially if you factor in 20 years of energy savings.

Old 10-20-07, 02:25 PM
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Some people do like them but you have to understand that what you gain in not having to store the water you spend in upgrading the power supply, in your case the gas line.

You need to make sure you size the unit properly for your families requirements.
You also need to make sure that your home's gas supply can handle the load along with any other gas equipment you may have.

I myself prefer equipment to be simple and have found from dealing with electric instant heaters they do need a bit more service that tank types for the simple fact they cycle more often.
Old 10-20-07, 04:32 PM
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I estimate our gas use to heat water was cut nearly in half by going to a tankless. In our case we didn't have the clearances for a tanked water heater (I don't know how the original one passed inspection) so tankless was a perfect alternative.
Old 10-21-07, 06:32 AM
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I have had tankless gas heater in a vacation cabin for several years. I doubt that we'll ever recoup the cost but that's not why we installed it. We just admire the efficiency.

OTOH our home has an electric tank type water heater. We have lived in this house for 23 years and replaced the water heater once. I replaced it myself so the expense was minimal.

We would like to replace with a demand heater but don't have gas available. My understanding is that the electric demand heaters can't match the gas operated in performance.
Old 10-21-07, 08:35 AM
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cwbuff brings up a good point about the differences in "efficiency" between gas and electric water heaters.

When comparing an electric tank to an electric demand type heater, electrically powered heaters of any type are all 100% efficient in that all the energy consumed is turned into heat.
The savings with this type of hot water tank are because you do not have heat loss from the tank when the water is stored and waiting for use.

Gas fired demand heaters can save more money if you purchase a high efficiency one.
The savings with this type will include better combustion efficiency.

If you are considering getting a gas one I would compare efficiency ratings along with how good the local parts and service would be.
Old 10-22-07, 10:09 AM
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Siesco Tankless

About a year ago after some research I purchased and installed a Siesco electric powered tankless water heater. The original ten year old electric powered tank heater is still in place but is switched off and is used as a holding tank for the incoming cold well water. The idea is to allow for some heat gain so the Siesco has less work to provide 120 degree hot water. The cost for the unit was around $700 plus an additional $150 for the cost of four circuit breakers and related wiring and some 3/4 in copper tubing and valves.
Works great and has been problem free.
Old 10-22-07, 12:02 PM
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I would like to see energy department charts on savings. I suspect there are savings, but not huge. A good tank type heater is about .62 energy factor. I think a gas tankless may be .8 There is still a lot of heat going up the flue. You do not have storage loss. You still have water loss if you are distant from the heater, and need to run water for a while. The initial cost is high, install cost is high, and if you have hard water at all, you must do annual maintenance. Your warranty will be affected if you allow lime scale to build up.

Right now, I see the main plus is that lots of people can take showers ( in succession, not all at once) or you can do hot water clothes or dish wash load after load to your heart's content.
Old 10-24-07, 08:55 PM
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Now if you have a modulating condensing boiler for heating, an indirect tank would be by far the best solution. Most efficient short of solar, no min/max flow restrictions like a tankless, no flue stack losses like a conventional gas... heck no moving parts except a dedicated circ, and it keeps the boiler from gunking up in the summer.
Old 11-12-07, 05:11 PM
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Short on space

I was also thinking about this cuz I would gain a closet and seeing I am in a condo it would be nice.BUT I would have to run a 4 inch stainless vent to the outside and that has causd me problems. Any Ideas. It would have to be run a good 10 foot with 2 bends. Thanks

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