I want to know how well the tankless waterheaters work? I have asked local tradesmen and they all try to talk me out of them. But, none of them have installed any. I plan to instal it myself. Any Ideas?
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You will be disappointed if you expect the same Niagara fall effect you have in your shower now. Temperature and flowrate are closely related. E.g the hotter you want the water to be the slower the unit delivers. Critical is also the incoming temp from your supply line (generally around 43 F) It takes time to heat the water up in the unit. If it is gasfired you might need a separate flue line, since most units require 100 000 BTU alone - not always permitted to run into an existing flue line. If you then have to open walls, floors, roof, it can get expensive, other than the unit itself. Will you live in the house that long until you recover the extra expense?
I tried to bring tankless waterheaters into Canada. My market research showed not much interest for the reasons given, mainly also because HO did not want to miss their flowrate of hot water.
I wonder if it would be usefull to have a tempering tank upstream of the heater...perfect also as an emergency H2O storage solution....
I dont think this would improve drastically. LIke, fastening a car on your rearbumper to help pushing the car in front.
There are tankless heaters with large capacities, now you are spending money!!
Tankless heater powered electrically with a solar hot water back up and photovoltaic panels to supply the electric energy.
We are getting there
The leading technology is in Germany. Check Stiebel Eltron on the net
I would think direct solar heating would be better...
I have no problem with installing them --- if some one is going to pay to have one put in, then that's my job.
I don't do much residential, so the tankless ones I install are in the Mbtu not Kbtu.
In my world efficiency isn't the issue it's how much hot water I can make & how fast can I make it.
Now having said all that, I have recommended tankless for some & told others to stay away from them.
Family size 2 or less it's a good deal. Family of 3 it's about a wash, & 4 or more you're better off with a good high efficient tank.
Where tankless beat tanks is standing heat loss, & being able to supply an endless amount of hot water at a slower rate ofcourse.
Tankless would not work for me, I have a wife & 2 boys---- 4 showers a day 2 loads through the dishwasher & couple loads of laundry. My tank never has a chance to sit idle except 11:30 pm to 4 am, that's not standing long enough for any noticeable heat loss.
On top of that I have a circ system, which is not a good idea when it comes to tankless.
Now if it was a vacation home, or just me & the misses I would install one in a heartbeat, I like that they don't take up as much space.
If you want to be over loaded with info & both sides of the spectrum do a search in the archives on tankless verses tank, there will be enough reading in there to kill enough time for ya.
"For instance, Hillary Clinton said in a recent visit that ethanol is 'a perfect example' of how we can wean ourselves from foreign oil. Of course, she has voted against measures promoting ethanol production not once, not twice, but 17 times during her six years in the Senate." The Federalist Patriot
ethanol? Too bad it takes almost as much OIL energy to produce as is to be had from teh ethanol. Too bad there is no where near enough available farm land to appreciably produce enough to make a dent in OIL demand. Too bad much of that land which would be required to be pressed in to agriculture is margin and far better as wildlife habitat and is also more erodible than land currently in production. Too bad that the price of ethanol has already nearly surpassed even the most expensive OIL based fuels. And too bad it is only viable if the government confiscates people's wealth, ie taxes you and me, just to make it competitive and is a massive farm subsidy. Other than that, it's a great idea.
Too bad Ethanol production in America has fueled a dramatic increase in the cost of tortillas in mexico and government price subsidies there on corn and a big increase in corn based animal feed here in NC. I'm still happy with my chickens corn to egg conversion though. Has there ever been a thread on builders chicken coops? Mine has a way cool built-in snake containment system.
Can someone comment on the need for inline particulate filter on the intake side of the tankless to prevent any clogging, etc?
Can the heating coils (or whatever these things have inside) get clogged?Darned town backflushed the waterline down the street and clogged up many of our coldwater side of faucet catridges, flush valves, etc. and in some cases at the shutoff valves under the fixtures.I'm overdue for major overhaul of our waterlines in the house to either PEX or new copper and inline filters, maybe just after the main shutoff, is part of the plan.Thanks for any insight.
Oh good gawd I need to change my tagline------------
You're the third to comment on it in non tavern posts ;-)
When it comes to ethanol & bio-diesel, I have an open mind, the quote is more about a politician contradicting themsevles from what they say & what they actually do."For instance, Hillary Clinton said in a recent visit that ethanol is 'a perfect example' of how we can wean ourselves from foreign oil. Of course, she has voted against measures promoting ethanol production not once, not twice, but 17 times during her six years in the Senate." The Federalist Patriot
My understanding is that the gas heated tankless are great. The big issue in my mind is the flow rate and the temperature increase.
I live in a condo in the NE and we have one person trialing an electric tankless (eliminating the tanks which burst and drain through the building is a big plus), there was one maintenance issue that has been resolved and he reports not having an issue with hot water in the recent cold spell.
The electric tested requires 2 220 lines... plumbing is straight forward.
The condo's I do have a central hot water system.
Gas can heat water faster than electric & when dealing with tankless flow & temp rise are the main issues.
I installed 2 RBI domestic tankless boilers for the condo project I just finished 100 degree rise @ 2.6 gallons per second.
But they are about 2.4 MBTU each---- that's a lot of gas.
Here's an electric tankless I put in for the Westin
View Image
It's a 480v 3 phase unit, basically it's 6 277v units piped in series.
BTW two 110v lines equals 220v, two 220v lines would equal 440v between the the two hot legs."For instance, Hillary Clinton said in a recent visit that ethanol is 'a perfect example' of how we can wean ourselves from foreign oil. Of course, she has voted against measures promoting ethanol production not once, not twice, but 17 times during her six years in the Senate." The Federalist Patriot
What makes you think that the electric tankless has no joints which can split and leak. If you read their owner's manual, they require a drip pan beneath them and the recommend against storing anything underneath that can be damaged by water. Anything that deals with water under pressure can and will eventually leak.
Bill
I'm not saying they can't leak, but I believe (no facts) that they are less likely too than tanks... especially considering that in a condo enviornment, there are individual owners that are either not aware of the risk of tanks bursting after the rated life, or are willing to risk it to avoid the cost.
In a building of 25 units, we seem to have one burst every other year.
I installed a Bosch unit for a HO whose old 30g water heater could not keep up with two showers at a time. He likes new technologies and was sold on the efficiency.
175,000 BTU/hr required much higher gas flow, so I had to re-pipe 40+ feet of gas lines at 2" and 1 1/4" to get capacity. $$$
Positive pressure flue required special SS parts with silicone seals - $330 for a 7-foot run.
I asked him two months later how he liked it. "Works great", he said, "but I'm not saving any money. Teenage sons now can shower as long as they want without running out of hot water, so gas consumption actually went up."
I had one in my house. I took it out after a few years. It is now serving to heat my garage (works very well as a small modulating, wall hung boiler).
I hated it because of the high pressure drop and because of the inability to respond fast enough to transients. The best there is cannot moduate fast enough to prevent cold and hot surges when other appliance are turned on or off. At steady state, like filling a large tub or taking a very long or many reapeaded showers, the endless supply of hot water is great. I would not buy one again. I would use one dedicated to a large demand, like the master bath whirlpool tub or the like. For a whole house with mutliple people, don't do it.