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LIL EVO
10-13-2011, 02:12 PM
Need a tankless water heater. Gas/Electric undecided.. Smaller home, not heavy demand for hot water aside from the normal.

Need recommendations for Brand, model, etc

brotherbenn83
10-23-2011, 07:25 PM
lmk how this thing works out for you. We just got a brand new old school water heater for free ($965 nat gas power vent (home warranty) in our new house and I think when that thing goes in the future this will be the direction I want to go.

Dr.Buick
10-23-2011, 07:28 PM
IDK how they work in a home but works on my floors great

awsomeears
10-24-2011, 07:12 PM
Unless you have a Large Family ( 5-6 and up ) and or a large Hot Tub I wouldn't get one !!!

If you have a liceneced contractor do one it could cost anywhere from $2000 to $3200 all depends on how much piping they have to replace, I have installed two of them personally and yea there nice but when they Break ( they will ) there is no local support and or companies that will stock the pcm boards or inducer motors just because...

Couple that with out of warranty calls and your talking big $$$ to repair these things down the road, I'm a strong believer in Over Engineering things ...

All in all I like standard water heaters that vent into a chimney, second would be a power vent ....

Compare Cost and Comfort and you won't be all that much ahead, most of the general public gets sucked into things that boast a payback as if you just struck GOLD !!!

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One plus with a instant but a power vent could be used is when a Home is built, not chimney easy of installation and location. Then IMO it makes sense because what you are saving on the initial purchase and construction will warrant it.

Plus you can find anyone to install a Standard Hot Water heater for around $800-$1200 and be done with it for 15 years with a slim chance of a break down, they are just so simple and economical....

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Dr. Buick is right they are nice and can be used for heating a floor, you just have to make sure the water heater is not OVER SIZED for the length and sq. footage of floor...

LIL EVO
10-24-2011, 08:02 PM
Going with a power vent. Too much to coordinate with the tankless at this point.

Al
10-26-2011, 09:46 PM
I have a tankless heater. It is AMAZING! It is about 24" wide, 30" tall and 10" deep. We mounted it against the wall where the old heater was. About 3 feed of additional piping was installed and the ventilation tube was extended about 6 inches. The total cost was about $1000, installed.

Al
10-26-2011, 09:48 PM
I have a tankless heater. It is AMAZING! It is about 24" wide, 30" tall and 10" deep. We mounted it against the wall where the old heater was. About 3 feed of additional piping was installed and the ventilation tube was extended about 6 inches. The total cost was about $1000, installed.

What's really nice is when you can fill up the washer with clothes, take a looooong hot shower, and get out just in time to start the drier.

MyP71Vic
01-25-2012, 11:28 AM
Where did you get it for $1000 and did that include the heater with install or just heater and you installed it? Ours is going out and will need to be replaced sooner rather than later. We run out of hot water after 30 min of shower time.

pOrk
01-25-2012, 11:58 AM
You can get good tankless units on sale at menards for around 1100, a buddy has one and installed it himself and its saving him 40/month.

LOL at having a standard water heater installed Brad, most people that are into wrenching on cars are more then capable of installing one of those themselves. Tank less takes a little more finesse...

awsomeears
01-25-2012, 12:09 PM
Yep been in the field for 7 yrs, don't know a thing ...

&

Good water heaters and menards shouldn't be used in the same sentence....

Will it * work * sure but for how long.....

MyP71Vic
01-25-2012, 12:52 PM
I have installed a normal one before but currently do not have a good torch for brazing. Running copper lines is not the issue but if I install it myself would anything be covered under a warranty or does the warranties not cover much of anything? Where would be a decent place to buy a tankless water heater or a tank one large enough to cover what we need? Thanks for the info!
-Nick

77thor
01-25-2012, 06:23 PM
... Good water heaters and menards shouldn't be used in the same sentence....

Will it * work * sure but for how long.....

LOL. I totally agree, they sell some real crap.

wrath
01-25-2012, 07:46 PM
I bought a Richmond/Rheem standard 6 year el-cheapo Mexican made 50 gallon electric for $250 exactly one week ago. I did the math and even though there are only two of us in the house and we take our showers at night (rendering the water heater unused for about 20 hours a day) it made no sense to get a tankless water heater. Electric water heaters are 100% efficient (mine heats the basement, it's not like it is in the garage like many in Florida). It didn't make sense to put a fossil fuel one in (there used to be one at one time) due to cost increase and fossil fuels are not any cheaper than natgas or nuke electric power these days.

Even if it only makes it five years, I still come out way ahead compared to others rated for a decade or so at four times the cost. Especially since the efficiency isn't that much greater and you're hedging on the water heater lasting that long. More expensive water heaters just have better insulation (marginal), multiple anode rods, and usually a titanium coated upper heating element. Oh, and heat trap nipples instead of plastic-lined nipples. Rheem still has the patent on their magnesium anode rods with the resistor built into the threaded end. If you were really crazy, you'd get a powered anode rod which is usually nothing more than a piece of titanium dangling in the tank with a small current flowing through it.

The old water heater in my house is almost 30 years old according to the serial number (old Rheem standard 85 gallon monster) and the only reason I replaced it was because there was so much ceramic lining missing that it was rusting profusely. I was ready to spend up to $1500 on a new tankless water heater but it just didn't make sense. If I were to build a new house, I'd probably put in several small electric tankless heaters.

Lastly, a medium tankless water heater takes 60amps. That would mean I could run the well and the water heater and that's it.

05caddyext
01-25-2012, 09:09 PM
Electric water heaters are not 100% efficient. They use more electricity than anything else in your home by far. They constantly keep reheating the water they store, even when not in use. And whoever said that you run out of hot water after 30 minutes, of course you do, most water heaters are 40-55 gallons. 1/2 hour is a lot of water. Also, with the amount of shark-bite type fittings available there is no need to be able to solder to install a water heater anymore. If it was installed properly the first time, re-installing a new one should be a piece of cake. The worst part is getting the damn thing in the basement. And hoping you get it home without damaging the tank. Most people lay them down for transport which is a no-no.

wrath
01-26-2012, 06:04 AM
Electric water heaters are not 100% efficient.

They are 100% efficient. ALL of the energy goes into the water as heat. Whether it stays there is another subject. Further, they are no less efficient as far as tank heat loss than any other tank type water heaters. A gas water heater is nowhere near 100% efficient.



They use more electricity than anything else in your home by far. They constantly keep reheating the water they store, even when not in use.

If you have an old refrigerator or a crappy electric dryer, they probably compete pretty well with the water heater. Unless your water heater sits in the garage, chances are it is only ~10% less efficient than a tankless. Personally, I don't care if it heats my basement up as it pretty much stays 58° year round and could use a little heat.

Until recently, natural gas was more expensive to heat water with than electricity. Right now the power companies have idled their coal plants and are running as much natural gas turbines as possible.


And whoever said that you run out of hot water after 30 minutes, of course you do, most water heaters are 40-55 gallons. 1/2 hour is a lot of water. Also, with the amount of shark-bite type fittings available there is no need to be able to solder to install a water heater anymore. If it was installed properly the first time, re-installing a new one should be a piece of cake. The worst part is getting the damn thing in the basement. And hoping you get it home without damaging the tank. Most people lay them down for transport which is a no-no.

1/2 hour is not a lot of water. That can easily be consumed by a dishwasher, a washing machine, and a quick shower. A tank-type hot water heater can deal with high volumes of hot water dispensing much better than a tankless (most of the medium-sized tankless water heaters are rated for 3.5-4gpm, my well puts out 15gpm@75psi and a 3/4" pipe can supply far more flow than that). You can also bump up the temperature of a tank-type hot water heater to get a little more time but you need to have anti-scald faucets or no retarded people living with you.

Shark-bite fittings are stupid. They're a great temporary solution but there is no way I'd rely on Chinese o-rings not to flood my house in ten years, especially ones that are constantly seeing temperature fluctuations. If you can't sweat a piece of copper or bond CPVC, you should probably leave it to someone else who can.

MyP71Vic
01-26-2012, 10:43 AM
Whether or not 100% of the energy is heating the water because it is heating the water or maintaining that temp all the time it is not really efficient. Tankless heaters heat the water as you use it so it is not wasting energy on heating water that is not being used. Those 20 hours a day your water heater is running and is not needed so that amount of time it is 100% inefficient. Based on your 4 hours of use a day your unit is 16.6% efficient because the other 83.4% of the time it is running while not needed unless you turn it off while not using it. This is the main reason I want a tankless heater.
-Nick

wrath
01-26-2012, 05:31 PM
Whether or not 100% of the energy is heating the water because it is heating the water or maintaining that temp all the time it is not really efficient. Tankless heaters heat the water as you use it so it is not wasting energy on heating water that is not being used. Those 20 hours a day your water heater is running and is not needed so that amount of time it is 100% inefficient. Based on your 4 hours of use a day your unit is 16.6% efficient because the other 83.4% of the time it is running while not needed unless you turn it off while not using it. This is the main reason I want a tankless heater.
-Nick

That is correct that tankless water heaters heat on demand. However, they require big wires (at least 8/3, up to 4/3) which aren't cheap. They also have limited flow for a set temperature delta. So, you might only get 4gpm out of something that takes 60amps. You could get cold every time a person flushes the shitter or washes their hands in the sink.

And you're clearly nuts because you do not have a 1500+ (more often 4500) watt element on all the time. It cycles constantly, usually switching between elements depending on water consumption. When you consume water, the top element trumps the bottom element.

Depending on insulation, heat trap, insulated pipes, et cetera, a tank-type water heater loses a couple percent of their heat each hour. Depending on the size and shape of the water heater, the cost of electricity, and the heat you keep your water at, it works out to like $50/year on the pessimistic side. I probably spend $600/year heating up water.

MyP71Vic
01-27-2012, 10:07 AM
For one my shitter uses cold water not hot and "Features: Delivers over 6 gallons per minute - enough to run two showers at once. Direct vent room-sealed combustion. Built-in power vent allows for vertical or horizontal venting. Provides ENDLESS supply of hot water. Electronic ignition plugs into 120V (no standing pilot). Space saving size and weighs only 67 pounds. Energy Star qualified. Remote thermostat model TSTAT2 available to digitally control output temperature." This will give plenty of water and does not need special wiring. Even if it would need new wire ran it is not far from the breaker box so that would not be much of an issue. This is an Aquastar 2400ES-NG Natural Gas Tankless Water Heater which is $1000 but would be easy enough to install. I would borrow a torch from my brother or dad to do this cause I trust brazing the lines more than fittings if brazing is an option then why not do it?
-Nick

pOrk
01-27-2012, 01:20 PM
Yep been in the field for 7 yrs, don't know a thing ...

&

Good water heaters and menards shouldn't be used in the same sentence....

Will it * work * sure but for how long.....

Believe it was you that also said that about the 55" Toshiba LED TV that I bought from there that's been working flawlessly since new. Just because you have been in the HVAC field doesn't mean you know EVERYTHING on the subject, nor do you need to post a cocky reply like that every time someone doesn't agree with you. I've been a metal fabricator for 5 years, does that mean I can and know everything about it? No. I also did NOT say you didn't " know a thing ".

eyeball
01-27-2012, 08:01 PM
I bought a Bosch FX135 somewhere around ten years ago from Home Depot. It was more than twice the price of a comparable tank heater. I bought the power vented one and installed it myself on an outside wall saving some space. Running larger diameter gas piping was something that I hadn't bargained for when figuring out how much it was going to save me. Because of the distance from my meter to the heater, I had to step up the gas pipe from 3/4" to 1". Another thing I didn't realize at the time of purchase was the wait for hot water at the bathroom sinks and in the kitchen. It didn't bother me, but my girlfriend sure complained about it. I eventually added a small, electric tank heater underneath the bathroom sink for washing hands and connected it to the kitchen sink as well. I had it figured out, after I first installed it, that it would take just under five years before I would make my money back and it would start saving me on the utilities. At the five year mark the board started to fail but only after ten minutes of use. It eventually got bad enough I had to fix it(was living by myself at the time, so i put off buying it till the cold showers got old). I bought one online and replaced it myself. The board cost me about $300. I added an additional heat shield to try and make this one last a little longer. It's been fine since. Another thing to consider is your washing machine. I bought a new high-efficiency LG last year. It's incompatible with the Aquastar as it takes hot water in short pulses when starting it's cycle. They use this to rinse the soap out of the dispenser. The forces the water heater on and off about a dozen times for every load of laundry. It is never on long enough to actually heat any water. I've been compensating by turning the hot faucet on in the stationary tub while the washer is filling. This kind of defeats the purpose of the high efficiency washer and the on demand hot water heater.
So yeah. Those on demand hot water heaters aren't all unicorns and sunshine.

jbiscuit
01-27-2012, 08:37 PM
I have a power vented AO Smith stand up hot water heater and this thing is the cat's meow! Can re-heat the entire tank in minutes. Almost endless supply of hot water. Granted this is a $1600 unit but I see no need to go tankless with this!

wrath
01-27-2012, 09:41 PM
For one my shitter uses cold water not hot and "Features: Delivers over 6 gallons per minute - enough to run two showers at once. Direct vent room-sealed combustion. Built-in power vent allows for vertical or horizontal venting. Provides ENDLESS supply of hot water. Electronic ignition plugs into 120V (no standing pilot). Space saving size and weighs only 67 pounds. Energy Star qualified. Remote thermostat model TSTAT2 available to digitally control output temperature." This will give plenty of water and does not need special wiring. Even if it would need new wire ran it is not far from the breaker box so that would not be much of an issue. This is an Aquastar 2400ES-NG Natural Gas Tankless Water Heater which is $1000 but would be easy enough to install. I would borrow a torch from my brother or dad to do this cause I trust brazing the lines more than fittings if brazing is an option then why not do it?
-Nick

The toilet comment I made is a pressure vs flow thing. It's difficult to explain. There is a real risk of running out of hot water because the flow through the heater is too great but what I was getting at was what someone else said, the toilet tricking the water heater to turn off briefly.

Bosch makes some of the best tankless water heaters, electric or dinosaur powered.

Chances are a large (high flow) liquified petroleum gas or natural gas water heater will require a new pipe and/or regulator. Otherwise if your furnace and your water heater come on at the same time you'll be short on fuel. I recommend finding the model of your furnace and look at what the minimum water column is for it, then cycle it. Most stuff needs at least 4" of water column at then the on-board regulator reduces it to whatever it needs. Awesomears is probably more familiar with it than me.

And yes, there are certain things you always want to have on separate breakers with one device on them (well pump, sump pump, water heater, range, dryer, and furnace) and depending on locality it is code.

Buy a MAPP torch for like $40 from Blain's. It makes soldering easy without overheating. Technically brazing is 800°+F sweating.

I'd spend the extra bucks for the 2700ES. It's like a grand on Amazon last I looked.

awsomeears
01-27-2012, 11:29 PM
I have a power vented AO Smith stand up hot water heater and this thing is the cat's meow! Can re-heat the entire tank in minutes. Almost endless supply of hot water. Granted this is a $1600 unit but I see no need to go tankless with this!

And believe it or not your unit is still a standard water heater with a Draft Inducer motor on it, check the tag of energy used per year vs a standard and you will see there practically the same..

There great !!!

MyP71Vic
01-28-2012, 01:15 PM
We are not buying anything till next year anyway so I have plenty of time to make the right choice unless ours craps out earlier. We do have a HE washer which I did not take into consideration for that. We have gas lines ran for our dryer, heater, and another one which runs outside for a gril hookup. There is a main point of connection which has larger pipe that I can tap into if needed. What else could be a potential issue? Thanks for all the advice so far I might end up staying with a normal tank heater if I can't find solutions to these.
-Nick

BR3W CITY
01-28-2012, 06:29 PM
if you want to go look at some thing, and talk to some knowledgeable guys there is a place called HotWaterProducts over on (i think) Tuetonia. They are a contractor supply for water heaters, insulation products and solar stuff. I don't remember if they sell customer direct, but they usually are happy to give a little knowledge out.
I had a good relationship with these guys when I was still with a mechanical.

wrath
01-28-2012, 07:07 PM
14" of water column is like .5psi. So, if you can imagine, there isn't a whole lot of flow because there isn't much pressure differential. You make this up by having large diameter pipes.

You can also get HE washers that keep the flow rate up for long enough to keep a normal tankless water heater from cycling. Most tankless heaters don't kick on until .5gpm but I have seen some with less. Our washer is a Maytag Epic Z (I think the same thing as a Whirlpool Sport or something) and it uses about 15 short bursts of hot water to fill the washer.

You can also get hybrid hot water heaters (small tank but instant on).