Add on tankless water heater

Aaron Ford · Feb 22, 2013

I would like to install one of those big bathtubs but everyone I know that has says that their wife doesn't use it cause the hot water heater is too small to fill it. So my thought was to place a thermostatically controlled tankless heater in line with the hot water supply. Does anyone know if this will work? Thanks. Aaron

oj · Feb 22, 2013

Gas or electric inline heater? and as my second question how good is your water? Municipal water is great as the solids/dissolved solids are low, but sometimes home well water has lots of minerals in it that will deposit in the heater and that's not good (ours does that in the workshop).

The gas ones are great if your water is good, electric ones can struggle to get the water hot enough if the flow is relatively high, and require a large supply cable (ours is is #8 i think).

504 · Feb 22, 2013

The small electric booster heaters would work, I have a full house electric now (three 50amp circuits to run it)and I had a gas before,gas is better.

da.bees · Feb 22, 2013

Sounds like a workable plan to me but if your tank can be used elsewhere or is half way or more through warranty,why not just change over to 100% tankless?
If you are installing a tankless,may as well reap all the cost savings benifits. It's not like it takes a huge tankless to fill a large tub,only takes a few minutes longer for a small or medium if it satisfys your other hot water requirments.

huntingreen2day · Feb 23, 2013

They make the tubs with the heaters in them. Just buy it that way. make sure it is wired to code.

ss55 · Feb 23, 2013

If your existing gas water heater is near the end of its life you might also consider replacing it with a high output gas water heater. High output units have a much larger burner, a better tank and a longer warranty than a standard water heater. The price difference should be an around an extra $200 over a standard water heater.

If you do get a tankless water heater, I agree it should become the main heater for the whole house to benefit from its extra efficiency.

Several people I know that bought homes with a big tub admit they only use it a few times a year if they use it at all.

don t. - 9n180179 · Feb 23, 2013

Wife just had to have one of them whirlpool tubs. We switched our tank(was dieing) to tankless. I can fill 80 gal w/no problems. Get the right size if you go whole house.

An option on my tub was an elect heater, to maintain the temp. I did not choose this option. The tankless refills it fine.

That all said....its been 10 years, we've used it 10 times. I've used it twice.
Big waste of....but she's happy(grin).

Two Dogs · Feb 23, 2013

I went the tankless (elec) route for a few months. It may be fine for filling a tub but in the shower I would freeze one minute and scald the next being on a well pump. They don't do so good in changing water pressure conditions. I gave that thing away and went back to the tank. Life is good again. TDF

glennster · Feb 23, 2013

aaron, i installed a corner unit jacuzzi tub about 10 years ago. the tub holds 87 gallons. i looked into a tankless type water heater, but they were pretty spendy. as my old 40 gallon heater was getting on in years, i replaced it with a 60 gallon. works out fine. also, if you have not yet bought the tub, get one with the heater installed. when using the air jets, it will cool he water quickly without the heater. having lower back problems for many years, the tub does wonders relieving pain. if you have kids, dont let em use bubble bath in the tub. it will look like an episode of the brady bunch with all the suds!!

JD Seller · Feb 23, 2013

The guys have nailed it pretty well. Get the tub with the heater in it. It will pay for itself shortly.

As for the tank less water heater. IF you are on a well they do not work the best. They need a real constant flow/pressure of water. They work best on a pubic water tower type of system. My sister put one in on her well. You where hot and cold depending on whether the well pump was on or not. The water would be cool when you where at high pressure and then too hot right before the pump would kick on. She took it out after about six months of fighting it.

da.bees · Feb 23, 2013

I'm suprised to hear so many complaints about irregular water pressure and noone useing a whole house booster tank and pump. Lower cost boost pump alows lowering wellhouse pressure which extends expensive well pump life and saves enough electricity to run the booster pump. I never gave much thought to this until I saw a very clever set up on a place where he had a problem with running his well dry during peak water usage. Seems he had a constant year around stream to the well but it was at a low rate of flow. He had a large elivated tank that was filled in 24 hour timed intervals. He said pump maintainance dropped dramaticly when the pump no longer pumped against pressure. He had some gravity fed outdoor hydrants and booster for the house. They said there was an unexpected benifit when power went off as it often happens during storms,they still had running water albeit gravity fed.

504 · Feb 23, 2013

I just want to add for anyone that has a tankless that switches from hot to cold, close the exit water valve some to slow the water flow,(keep the water in the heater a little longer) that will end the temperature swing and you will never notice any difference in the shower flow.

JD Seller · Feb 23, 2013

da.bees: The issue is not the well pump having problems pumping it is how the systems work. A well with a pressure tank will have a 20 PSI low to high range. That is just how they work. An example of this is my system it kicks the pump on at 40 psi and off at 60 psi. The flow changes over the the pressure range. My well was tested at 100 gallons a minute flow. So water supply is not an issue.

A private tank system is a problem in cold climates. Plus you need a tall tank to have much pressure. Years ago they would have tanks up on the windmill towers in the warmer areas. Also you have a problem keeping stored water fresh. That is one reason public water is treated.

da.bees · Feb 24, 2013

(quoted from post at 00:09:10 02/24/13) da.bees: The issue is not the well pump having problems pumping it is how the systems work. A well with a pressure tank will have a 20 PSI low to high range. That is just how they work. An example of this is my system it kicks the pump on at 40 psi and off at 60 psi. The flow changes over the the pressure range. My well was tested at 100 gallons a minute flow. So water supply is not an issue.

A private tank system is a problem in cold climates. Plus you need a tall tank to have much pressure. Years ago they would have tanks up on the windmill towers in the warmer areas. Also you have a problem keeping stored water fresh. That is one reason public water is treated.

Well JD in your case a $40 pressure reducing valve set to 39 psi is all it would take to stop the house pressure taking a mind of it's own. The system I described eliminates several different issues,all of which that rancher had at the time. I made reference to pressurizing pervisions and gravity feed only happened at a couple of outdoor hydrants and when electric service went down which beats no water at all. Anyone not living in the sticks or tornado belt probably never worries about that kind of power interuptions. As in most things,"you milage may vary".

JD Seller · Feb 24, 2013

da.bees: I had not thought about the reducing valve. I was just outlining one of the issues with the tankless water heaters. They also are not the best if you have hard water. Even the salt left after a water softener will cause issues with them.

I will just stick with a standard old water heater. They are proven and simple. The energy saveed is not that much if you use much hot water. They save more if you are not using much hot water.

As for worrying about losing power. That has always been a worry with livestock in confinement feeding yards. I used to have a PTO generator but a few years ago put in a stand by propane powered generator. That is the only way to go. Many fewer headaches when you lose power.

Have a good day!!!

Add on tankless water heater

Aaron Ford

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oj

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504

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da.bees

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huntingreen2day

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ss55

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don t. - 9n180179

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Two Dogs

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glennster

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JD Seller

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da.bees

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504

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JD Seller

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da.bees

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JD Seller

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