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View Full Version : Thinking of switching to a tankless water heater.



Aren Jay
03-12-2008, 09:14 AM
Does anyone have one?

cyclopsram
03-12-2008, 09:33 AM
is Home Depot forum interlinked by mistake?

sailsmen
03-12-2008, 09:45 AM
Make sure the gas supply is sufficient.

duhtroll
03-12-2008, 10:09 AM
I was going to do that a couple years ago and was told by a couple of the plumbers I asked who sold them that the water pressure sucked. Technically the one I was looking at was rated for 2 uses at one time (like a shower and dishwasher) but he said I wouldn't have been happy with it.

Since they made a lot more selling the tankless (they were like $2K installed at the time) I figure he was telling the truth -- or he also worked for the gas company.

I haven't looked at them in a couple years -- maybe they have gotten better.

fastblackmerc
03-12-2008, 10:57 AM
I had one installed last year.


It's made by Rinnai (the only one I'd recommend after doing 2 years of research)
Had it installed by the local natural gas company
They increased the size of the service at no charge
Took 2 guys 5 hours to install
Gas company provided free financing for 12 months, just added it to my monthly bill
Most require a professional installation to keep the warranty in effect
Most makers have an interior & exterior models
Exterior easier to install
I went with exterior, looks like a white briefcase on the side of the house
The model I have supports 3 uses / users
Most have electronic temp controller (mine is set at 110deg)
Will supply 110deg water for the 3 uses as long as I don't run out of gas or water
Tiny increase in gas bill


Only drawbacks are the cost & you tend to take longer showers because the water always stays hot.

PM me if you want to discuss more.

Grifter
03-12-2008, 01:45 PM
did you used to have a gas water heater before you went tankless?

MERCMAN
03-12-2008, 01:48 PM
Installation sounds like a "tankless" job ! :rofl:

Bigdogjim
03-12-2008, 01:53 PM
Tankless is the way to go....................

Cheeseheadbob
03-12-2008, 01:55 PM
Everything Jim said. I had mine mounted inside a closet in the lower level of my house. The plumbers had to knock a small hole in the exterior wall for the vent, but it is hardly noticable from the street. The only, and I mean only drawback is that it may take a little longer for the hot water to reach to furthest part of the house since there is not a bunch of hot water sitting in the pipes. A very small price to pay for the overall benefit these units provide. BTW I have a commercial unit in my house, but the residential units are basically the same, only smaller and the temp control does not go as high. If I wanted, I could have constant 160 deg water... great for getting those greasy dishes clean!:D
I had one installed last year.

It's made by Rinnai (the only one I'd recommend after doing 2 years of research)
Had it installed by the local natural gas company
They increased the size of the service at no charge
Took 2 guys 5 hours to install
Gas company provided free financing for 12 months, just added it to my monthly bill
Most require a professional installation to keep the warranty in effect
Most makers have an interior & exterior models
Exterior easier to install
I went with exterior, looks like a white briefcase on the side of the house
The model I have supports 3 uses / users
Most have electronic temp controller (mine is set at 110deg)
Will supply 110deg water for the 3 uses as long as I don't run out of gas or water
Tiny increase in gas billOnly drawbacks are the cost & you tend to take longer showers because the water always stays hot.

PM me if you want to discuss more.

Leadfoot281
03-12-2008, 02:25 PM
I use an outdoor wood boiler to heat the house and my water. My tap water is between 180 to 190 degrees and never runs out.

It takes about 2 minutes to brew a pot of coffee.:D

Bigdogjim
03-12-2008, 04:17 PM
Also at my house the fellow I bought it from has a "few" vetts and had a hot water outlet on the outside for washing his cars:)

Hot water is great for washing your car:) :up:

rumble
03-12-2008, 06:00 PM
My daughter and son-in-law went with two of them when one of their regular gas water heaters croaked.

The only down side I see is they make a lot of noise when the burner is going. Probably want to install it in the garage. Otherwise it seems to be the way to go.

Bradley G
03-12-2008, 06:22 PM
I looked into one and my friend, who owns a plumbing company told me not to get one.
We are on a well and he said they have problems with the internals getting gunked up with mineral deposits.
I got the 50 gal quick recovery, I can take a shower for an hour!

Pat
03-12-2008, 06:49 PM
Neighbor next door built himself a new two story house and put in two tankless systems in the second story. He really likes 'em no problems plenty of hot water. We are in the city with plenty of water pressure and the water isn't full of minerals like Arkansas. He also installed water pre- heaters near the sinks because the water has a long way to go from the tanks to the remotest bathrooms.

mongo
03-12-2008, 09:15 PM
That sounds like alot of work to do a simple task that has been done the simple and easy way for about 100 years! I am a licensed, and have been a plumber for 20yrs. Plain and simple, these are not designed for American homes.It is perfect if you have one bath and have a desire to run hot water forever.Up front costs are huge,150-200,000 btu usage to 45-50,000 and dont forget nothing works forever. Repair costs are steep. I dont see how you could ever recoupe your money.

Tom Doan
03-13-2008, 04:46 AM
I have a big one at the beach house and a small one at home. I love them, save me 50% a year in gas bills, payed off in 6 months. Down side, the small one will only run one facet at full force in a 1/2" copper pipe or if the wife turns the washer on both will get half flow but it's still hot and will stay hot for as long as the facet is open. The big one at the beach house will run 3 showers at the same time full blast which is what I bought it for. Little one cost 600.00 and I did a self install in a hour, big one 750.00 and had a plumber install in one hour. This is the greenest thing you can do that gives so much performance at the same price as a water tank unit.
P.S. The big one is about 2" bigger in all dimensions than the small one and that is the size of your bed pillow.Tom

High-C
03-13-2008, 05:56 AM
I have to agree with Tom... There really are no down-sides to the tankless technology... The only problem you can have is an inexperienced installer. They MUST be sized correctly. The tankless heaters "flow" is based on the GPM (gallons per minute) demand of the fixtures in the house. For example, if you have five fixtures that, if all on at the same time, require 6 GPM then 1 regular residential unit will work at a 55 degree rise (60 degree incoming water temp with a desired temp of 115 degrees)... If any combination of these fixtures are used you will always have maximum flow, but if your GPM demand is more than the maximum flow of the heater at the desired set temp than the heater will decrease flow to maintain a constant temp... Therefor sizing is important. As it was stated earlier, the BTU demand of these heaters are much greater than a traditional tank-type heater so the gas line size/input may need to be increased as well. I can tell you this though, it costs much less to heat water only when you need it than it is to keep 75 gallons at 115-120* 24 hours a day...

Sorry for the rant... - C

SID210SA
03-13-2008, 06:09 AM
I have an electric one at work and it sucks!!! We are going on our 3rd one in 4 or 5 months. Its a REDRING PowerStar tankless water heater.
It is only being used for a one person bathroom and cant even handle that!!

Dragcity
03-13-2008, 06:18 AM
I looked into this too. What I have found out thus far. In the northern climates, where supply water can get very cold, they will not work in supplying hot water to a user. The rise in temp is maxed at about 65 degrees F. Here in Buffalo, our water comes from Lake Erie. In the winter, the lake freezes. The water is 32 to 34 degrees for months around here. 97 to 99 degree water is barely a "Hot Shower".

I am passing on it. I understand you can put two in tandem to get the temp increase needed in cold climates. I would suspect that would not be so effecient, and a costly initial outlay.

Just my two cents.

I wish I lived in a milder climate.

High-C
03-13-2008, 06:23 AM
The electric tankless heaters do suck... They aren't nearly as efficient. The only electric tankless heaters that are remotely okay are Eemax point-of-use heaters that go under a lav or two to run a couple lav faucets etc...

Badger
03-13-2008, 07:19 AM
But the ability to continuously run hot water becomes addictive. Methinks the efficiencies are negated by the icreased water usage.
Anywho my radiant floor heating system can not use an instant type heater. No complaints with my 50 gallon tank. In fact I've IR'd it. Not that much loss and simpler is a lot of times better.

fastblackmerc
03-13-2008, 07:24 AM
did you used to have a gas water heater before you went tankless?

Yes. The main savings is not keeping 40+ gallons of water heated when you aren't using it.

Marylandrauder
03-13-2008, 10:56 AM
Just this past week an article in the Washingto Post had the same comment-said it would take 12-15 years to pay for itself(in savings over a standard 50 gal. unit).

Cheeseheadbob
03-13-2008, 11:08 AM
But it will last indefinately, whereas a standard hot water tank should be replaced every 10 years at most. It is just like smart financial investing, go for the long term payout, not the quick reward.
Just this past week an article in the Washingto Post had the same comment-said it would take 12-15 years to pay for itself(in savings over a standard 50 gal. unit).

duhtroll
03-13-2008, 12:05 PM
Normally I would agree, but I have a 40-gal unit in my house that is from 1985 which will scald you for 20 minutes, at least.

I ain't letting it go until it goes on its own. :)


But it will last indefinately, whereas a standard hot water tank should be replaced every 10 years at most. It is just like smart financial investing, go for the long term payout, not the quick reward.

Dr Caleb
03-13-2008, 12:18 PM
Just this past week an article in the Washingto Post had the same comment-said it would take 12-15 years to pay for itself(in savings over a standard 50 gal. unit).

I don't understand where all the misinformation comes from, or is it just a difference in our locations?

http://www.directenergy.com/EN/Alberta/RES/Pages/SPO/SPOWaterHeater.aspx

a 30% - 40% monthly savings on my gas bill means $50-$70 a month. We get up to a $1000 rebate for improving fuel efficiencies in our homes, so $1200 cost for the most expensive Rinnai model means it'll pay for itself in 20 months. 4gpm is nearly as good as my water supply gets.

I know many people who have switched, with nothing but good things to say about tankless hot water. (no one got an electric.) I know people with electric water heaters (no natural gas available, just propane) and they get ***** every month on utilities. Something like $400 just to have hot water. Tankless+propane is a godsend for them.

Aren Jay
03-13-2008, 12:42 PM
My Sister has the expensive house hot water heater with the pipes in the ground behind her house. I do like going to her house as she has unlimited free hot water. System does cost around $50K though but she saves about $1000 about month on heating and hot water costs. (Big House).

She has lived there for 3 years now and in a couple more it will be paying for itself.

I just use, like almost everyone in Alberta, a Gas powered Water tank/heater. From the looks of it, I do not use huge amounts of water, but I do run out of hot water on every shower I take in 11 or so minutes now. My Tank/heater is 16 years old an not working very well anymore.

For the same Price I think I will upgrade to a tankless system. I don't run more than one hot water appliance at a time right now, (current system drains the hot water in 4 or so minutes if I do) I do have unlimited cold water. (yes I pay for it) But I pay more for Gas than water.

Yes I probably will increase my showers by 10 minutes. But that will make me happy so it really doesn't matter.

Dishwasher will not take any longer, nor will the washing machine, so I should see some savings. Atleast I should be happily hot watered in the shower.

High-C
03-13-2008, 02:06 PM
There's your answer to the cold weather... Geothermal heating and cooling and a minimum water temp of +/- 50* year round... Add a digitally controlled low BTU boiler and some radiant heating/cooling loops and you have heating and cooling with tons of savings... I wish I were building a house right now. There are some cool options out there. :cool:

GreekGod
03-13-2008, 03:42 PM
But it will last indefinately, whereas a standard hot water tank should be replaced every 10 years at most. It is just like smart financial investing, go for the long term payout, not the quick reward.

Nothing lasts indefinately! What keeps the boiler from getting "limed up", like a tank type heater does? If it gets internally coated, efficiency will be reduced.

The actual life of tankless heaters seems unknown/unadvertised. Most people know a tank type heater lasts 10 to 15 years.

High-C
03-14-2008, 04:57 AM
The heaters are actually just as "reliable" as a tank type heater or even more so. The heating element that could "lime-up" is the copper or now stainless steel heat exchanger and because it only sees use while the unit is running (vs holding water for 24hrs a day) it actually stays fairly clean. The material is also different than a cast iron boiler or a steel water heater tank. It is more resistant to corrosion and scale. This heat exchanger is also modular so if it needed to be replaced, the job is comparable to changing an element on an electric heater. The other upside is that if the heat exchanger were to clog or restrict flow, the unit will sense this and throw an audible alarm combined with a code that can be read by the homeowner or servicing plumber. This takes the guess work out of diagnosing a problem... This is fixed by rinsing vinegar through the unit with special taps that are on the heater for this reason. This can be done by the homeowner prior to a service call and walked through over the phone. This is also recommended every 6 - 12 months if you are on a well system without a water softener etc or in an area with hard water. I hope that you guys don't mind me ranting about these things but it is a technology that many people do not understand or people in the industry tend to put down to resist change. I guess to old adage still holds true that "you have to pay to play" and if you want the highest technology and efficiency, you will always pay more for it up front... Not that there is anything at all wrong with tank-type traditional water heaters. They are cost effective and less expensive in most cases, but this really is the future of where the residential hydronics market is going. Wow... I feel like magindat talking about speaker performance and amplifier efficiency... ;)

GreekGod
03-14-2008, 11:56 AM
The heaters are actually just as "reliable" as a tank type heater or even more so. The heating element that could "lime-up" is the copper or now stainless steel heat exchanger and because it only sees use while the unit is running (vs holding water for 24hrs a day) it actually stays fairly clean. The material is also different than a cast iron boiler or a steel water heater tank. It is more resistant to corrosion and scale. This heat exchanger is also modular so if it needed to be replaced, the job is comparable to changing an element on an electric heater. The other upside is that if the heat exchanger were to clog or restrict flow, the unit will sense this and throw an audible alarm combined with a code that can be read by the homeowner or servicing plumber. This takes the guess work out of diagnosing a problem... This is fixed by rinsing vinegar through the unit with special taps that are on the heater for this reason. This can be done by the homeowner prior to a service call and walked through over the phone. This is also recommended every 6 - 12 months if you are on a well system without a water softener etc or in an area with hard water. ...

Thanks for the info...it sounds good, but...

1)"The actual life of tankless heaters seems unknown/unadvertised"...and

2)"Nothinglasts indefinately"...so ?...and...

3)I can imagine a replacement heat exchanger would cost as much as a whole new unit.

Menards (a midwest USA big box lumberyard seller) has them on sale frequently. I have been looking at them for years, and the manufacturer doesn't advertise their questionable deficiencies.

Cheeseheadbob
03-14-2008, 12:50 PM
You are correct, Sir! "Indefinately" was perhaps a little hyperbolic.:D
Nothing lasts indefinately!

Aren Jay
03-14-2008, 01:00 PM
That is true "Nothing" does last indefinitely. I have had quite a bit of "Nothing" and it is still there. It never seems to go away on it's own.

Tom Doan
03-15-2008, 07:26 PM
Yeah, well mine came with a 15 year warranty If I installed it and a 20 year warranty if I had it done by a pro.