Anyone have experience with tankless water heaters

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Like the title asked, does anyone have experience with natural gas tankless water heaters> More importantly, are they reliable? Any brands better than others? My three year old, kalifornia mandated, low emission water heater has failed yet again. It will be another $200 to get the plumber out here again because of the low emission garbage pilot light will not stay lit. My old water heater lasted over 10 years before the tank rotted out due to the hard water out here. Never had a problem lighting it or staying lit. Since I can't get a regular water heater out here, I was thinking tankless. Any input apprciated.
 
I have 4 of them.

In my main house in Santa Cruz I have a Propane unit that has been excellent, and an electric for backup when propane is scarce. The propane one is lit automatically with a "D" cell.

In Tarija, where I have my remote office and home, I have two on natural gas. One serves the kitchen and two upstairs bathrooms, the other serves the master bath and the housekeeper's bath. One has a pilot that goes out on windy days. The other has the battery.

The advantage is that when you need hot water, it is there. No waiting for it to heat up or leaving it on while you are away. You still have to wait for the hot water to reach you, and the capacity doesn't always compensate for the distance. It was 19 degrees here last week and water cooled getting to the shower. It takes forever to fill the jacuzzi.

You have to get used to the settings and controls, at least on the ones we get here. If you turn the water on too much, or a second person showers while you are, the water gets colder since too much water is flowing to heat.

If you don't have enough water flowing, it shuts down from overheating.

I have one apart now as 4 of the wires inside melted. They are the type you might expect in a flashlight, and granted all they carry is the D cell current to light it, but the ambient temp gets up there.

There may be much better units available in the US, but those are what we have.
 
I had a whole home gas condensing tankless installed almost two years ago, since you have gas I recommend it over electric. My neighbor went with electric and had three units installed, two burned out in less than a year. I contacted a local contractor and they recommended Rheem, I'm hopful it will last a long time, water usage is extremely low and we get extremely hot water on demand almost instantly.

15 year warranty on the heat exchanger itself, all other parts is 5 years.
 
Take a road trip out of state and buy a better hot water heater, or order a better hot water heater online?
Even if the plumber refuses to install a non-complying unit (and I'd bet he won't), install is pretty easy for anyone with minimal DIY savvy.
 
When we first built our house we installed a propane-fueled Bosch tankless water heater as our only source of hot water. It proved troublesome and from time to time provided a cold shower for my wife, who was not amused.

We upgraded the system so that we have water heated in panels on the roof and then stored in a normal hot water tank (without power to the heating element). At this moment, the water temperature in the tank is 135 deg F. When we draw on hot water, the water leaves the tank and passes through a Rennai tankless water heater. If the temperature of the water falls below 125 deg F, then the Rennai kicks on and brings it up to that temperature. Works like a charm.

The Bosch had a pilot light which would go out occasionally. The Rennai plugs into a wall socket. We are off the grid, making our own electrical power, so we always have power and hot water.
 
My experience with them is in commercial/industrial settings and they do save money. Don't use with hard water, as jrustles points out. You better off buying a bit bigger than you need rather than one with too small capacity. In some cases, a small commercial one is better than a large domestic one.
 
Originally Posted By: Sunnyinhollister
Like the title asked, does anyone have experience with natural gas tankless water heaters> More importantly, are they reliable? Any brands better than others? My three year old, kalifornia mandated, low emission water heater has failed yet again. It will be another $200 to get the plumber out here again because of the low emission garbage pilot light will not stay lit. My old water heater lasted over 10 years before the tank rotted out due to the hard water out here. Never had a problem lighting it or staying lit. Since I can't get a regular water heater out here, I was thinking tankless. Any input apprciated.


I, too, have a Kalifornia-style FVIR water heater, but mine hasn't given me any trouble. Do you know if your thermocouple is bad, or what? How many times has it failed? I ask, because pilot light troubles can also be caused by high winds and/or improper flue venting. I realize the new pilots are teensy, but they should stay lit under normal circumstances.

As far as tankless goes, I've installed a number of Noritz heaters without any callbacks. I'm a Rinnai certified installer (not a big deal, just a class you have to take), so I've put in a few Rinnais also. Both Noritz and Rinnai seem fine to me.

If you install a new tankless in place of a storage-tank water heater, you will have to replace your venting with new stainless-steel venting. This may or may not be overly expensive depending on your situation. If you use a Rinnai, you will need to use Rinnai concentric venting, which is pretty expensive, but not bad if you don't have to go far. There are a lot of variables with tankless.
 
My Father lived in a house that was built for them, and They had Bosch thankless water heater. House is about 12 years old now, no problems at all as I know.
 
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Originally Posted By: Stelth
If you use a Rinnai, you will need to use Rinnai concentric venting, which is pretty expensive, but not bad if you don't have to go far.

Mounted directly to a wall that can be cut makes it very easy and inexpensive.
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We have a four & a half year old Rinnai that's been pretty much flawless for us. I do wish they put some sort of bug-screen in the intake venting.. (concentric) but other than that, it's been good. I vinegar-flushed it at three years but that could be like the 3k OCI crowd.. it wasn't asking for it yet. (Softened water helps).

See what the next ten years brings.
 
People think tankless water heaters are something new. Back in 1960-1961, when I was living in Nicosia Cyprus, I had a tankless water heater in my house. Worked great. Turn hot water on and the gas would light with the flame in the center of the water filled coils. The faster the water flowed, the higher the flame, all within the unit.

Never had problems with it. Don't know if today's units are as good or dependable as the one I had.
 
If it has seals on the inner coaxial pipe be sure to use them and if it comes with a dried up tube of red silicon, purchase a new tube or a calking gun tube of the red high temperature silicon. People who do not do a good job of sealing the pipes end up with them not staying on because of exhaust leaking into the intake air.
 
I'm on my second one in about 10 years, and will soon be on the third. The first was a Bosch. It was troublesome from the beginning. My second was a Richmond and it failed under warranty. The replacement was installed about a month ago and it has a very load moan every time you turn on the hot water. (It sits in the basement and you can hear it loadly on the second floor) I was hoping it would go away, but it hasn't.
If you go the tankless route, I would recommend that you install a water filter immediately in front of the inlet pipe. They do not like contaminants of any kind. Also, they recommend that you flush these out yearly with vinegar. (You can see a few examples on YouTube)
As far as fuel usage, you will save money, but I think they require more maintenance, on average.
 
I bought a Rheem tankless natural gas heater from home depot.
http://www.homedepot.com/p/Rheem-EcoSens...54#.UfXdKm1huSo

I had to upgrade my copper water lines from 1/2 inch to 3/4 inch as well as having 3/4 gas supply to the tank.

I never run out of hot water now and I don't have to worry about my kids using too much hot water although they do like to take longer showers now. The unit is more quiet than the power vent tank that I replaced. Costs are more initially, but you will make up for it in the long run with lower gas consumption. A tank water heater might last for 10-15 yrs before it rusts out. Tankless are supposed to last 25 years but need an annual vinegar rinse.

I will never go back to a water tank ever again.

Regards, JC.
 
We have a tankless in our vacation home, but the main dwelling has a tank. The reason being, if there is ever an interruption in water supply, I should have 50 gallons of potable or easily treatable to be potable water. Pilot lights help maintain the hot water so its not all a waste of gas. I also know I can take a hot shower without electricity. Every tankless water heater I have seen requires a source of electricity even if it is gas.
 
I have an electric until made by Stiebel Eltron. No problems with the unit in 4 yrs. We have averaged a $25.00 month drop in our power bill. It does take two 50 amp breakers to run it so its better off installed in new construction or a major remodel.
 
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