Tankless Hot Water Heaters

[<josh]

My Takagi draws little enough current that if the power is out, I can run it off the pocket-sized power inverter I keep in my car. No added cost for that, I already had the inverter anyway.

[<josh]

My Takagi draws less than an amp maximum, and that&#39;s briefly while the blower is clearing the exhaust after the burner shuts off; most of the time it&#39;s much lower draw. Any decent UPS can handle 120W loads.

[<josh]

Remember that when you do eventually need to replace it, you probably won&#39;t be re-doing the gas plumbing, wiring, or potable water plumbing for it. You&#39;ll just remove the old unit and install a new one.

Your N-069M-OD sells for under $1,000 on-line. My Takagi is under $900 these days. Replacement is simple enough you can do it yourself if local code allows. (OK, be honest, how many people take out the required permits to replace their tank water heaters?)

[hallerb]

My Takagi draws little enough current that if the power is out, I can

Odd the Takagi website doesnt list current consumption,&#39;

In any case those who vent up a chimney are probably low power users in comparison with direct vent models that must use a blower & motor for exhaustion of course chimney type often need chimney upgrades because the high BTU models are perhaps 3 times the BTU of a average forced air furnace.

this makes me wonder about that big flue exhausting heated home air

24/7 all winter long... humm I wonder the same about my standard hot water tank and furnace, must be like leaving a big window open permanetely.

wonder if anyone has ever done studies of flue heat losses?

Because oif this awhile ago I had decided to go with forced vent standard high BTU tank.....

[CptDondo]

Don&#39;t most current building codes require outside combustion air these days?

--Yan

[hallerb]

many furnaces and most standard hot water tanks use room air, a bad idea if you ask me.

[Gary KW4Z]

Thank you to everyone that contributed on each board. While I haven&#39;t totally made up my mind about what I will do, and I have plenty of time to do that thankfully, I am leaning (due in part to opinions on these newsgroups) to staying traditional, with a 50 gallon high efficiency, Gas, Hot Water Heater with a long warranty. Being that there is mostly the wife and myself I think that will due us even when we have the grandchildren over.

Again thank you for each of your input and I will continue to follow this thread and also do research into past question regarding tankless water heaters. Could be by the time I actually build things will change again but for now I&#39;m changing my mind, back to the Gas Tank model. The reason is that even with the cost savings of the tankless I&#39;m very concerned that they will not hold up over as long a time as tanks have proven to last and apparently the manufacturers don&#39;t necessarily think they will either by the warranty length they assign to them so that&#39;s my reasoning for changing my mind.

[hallerb]

Theres no harm in getting a 75 or even 100 gallon high BTU tank. regular tanks are about 40,000 BTU my high output is 75,000 BTU 50 gallons. thats a lot of water. by the time i am done getting a shower, dressed and go downstairs with the laundry the tanks burners are shutting off, and my shower has the flow restrictor removed:)

[JimR]

[snip]

Having experience with both tankless and conventional, I much prefer conventional. Consider this:

We have a standard large tanked water heater which serves kitchen, laundry and two bathrooms. When we renovated the back half of the house we added a small cabinet in the new hobby room with a second water heater tank inside which serves only the adjacent master bathroom. This gives us hot water within seconds.

( We also did a few other unconventional things such as adding an outdoor sink and shower so that you can clean up and shower after working in the garden or coming in from fishing. Since the "utilities" side of the house (with the shower, plus nearby well pump, central air conditioners, etc.) is behind a 6&#39; concrete block and tile wall privacy is not a problem.)

With this experience, during any future renovation I&#39;d consider another hot water tank, perhaps a low-boy unit or attic unit, for almost-instant hot water for one or more of the other bedroom suites -- Regards --

[<josh]

It&#39;s in the PDF manual, towards the end.

Haven&#39;t done a formal study of it, but while testing for drafts I blew smoke around our water heater on a cold day, didn&#39;t have any noticeable convection up the flue. But our flue is mostly horizontal, definitely needs the blower.

Our long-range plan is to convert it to use outdoor combustion air once we get around to the finished cabinetry in the pantry where it sits.

[Dan_Musicant]

:In article , : [e-mail] says... :> :> # Fred # wrote: :> > And I guess a UPS that would supply power for more than 1/2 :> > > hour or so is going to be costly. So&#39;s a generator. :> > >

:> > > Dan :> >

:> > Should be cheap as not much power required to control the gas fired unit. Go :> > to any office or computer store and get one suitable for you unit - should :> > be under $100. You need to replace the UPS battery once every few years. :> :> ahh check the current use of the tankless, if it uses a fan for exhaust :> you may need a really large UPS. : :My Takagi draws less than an amp maximum, and that&#39;s briefly while the :blower is clearing the exhaust after the burner shuts off; most of the :time it&#39;s much lower draw. Any decent UPS can handle 120W loads.

You know, I really don&#39;t think it&#39;s worth it to get a UPS just to insure I have hot water if my power goes out. I&#39;ll be a lot more concerned about the power and especially the food in my refrigerator going bad. Hot water? Holy smokes, my ancestors had to build a fire to get it. I&#39;m not going to be such a pussy about it.

Dan

[Dan_Musicant]

:In article , : [e-mail] says... :> :> It works OK. I realize that at this point I&#39;m on my own and I just hope :> it lasts a real long time because I don&#39;t presently like the idea of :> spending big bucks to fix or replace it. :> : :Remember that when you do eventually need to replace it, you probably :won&#39;t be re-doing the gas plumbing, wiring, or potable water plumbing :for it. You&#39;ll just remove the old unit and install a new one. : :Your N-069M-OD sells for under $1,000 on-line. My Takagi is under $900 :these days. Replacement is simple enough you can do it yourself if :local code allows. (OK, be honest, how many people take out the :required permits to replace their tank water heaters?)

Good point. I suppose if I still live here and my Noritz goes bad I might well opt for a similar tankless to replace it since the gas and plumbing are all right there, and they were AFAIK professionally and well-installed. To put in a tank water heater would be problematical because it would have to stand away from the wall at least enough to clear the dryer vent. The contractor who authorized all this told me I couldn&#39;t do that because I would not be able to strap and support the tank. This is earthquake country.

[<josh]

Frozen casseroles from the deep freeze will keep the fridge cold enough that milk lasts for many days. Think of it as an icebox with edible ice. Some of the frozen stuff is going to thaw anyway, might as well put it to use.

While the house was jacked up getting a new foundation, we spent 6 weeks with the gas disconnected. Boiling water on the stove for baths gets old fast when you have twin toddlers.

[Dennis]

Not for nothing, but my 40 gal gas (spec grade) was installed when the house was new in 1978 and is still going strong.

Tankless are really good for cabins and the like. Don&#39;t believe I would put one in a new home unless it serves a single fixture located a long distance from the water heater.

Just doesn&#39;t make any cents (don&#39;t forget to figure additional costs for increased gas lines, larger meter, assoc. as well.)

[Dennis]

Dan, there are straps made specifically to anchor water heaters not located directly aganst a wall. In fact, most of the installations I&#39;ve inspected did not bear directly on the wall in back of the heater. In seismic D1 & 2, you only need to strap in upper and lower 1/3 to withstand movement, and there are many ways to accomplish this.

[jbrowne001]

We put in a Paloma PH6-DP in 1987, and have never made a repair (although I bought a similar unit, for parts, for $50. about 15 years ago- hard to find these old units). My local propane distributor has one like it for their kitchen/ washrooms. We also cook with gas. Our water pressure is about 20psi max (gravity system from a spring up the hill) and this thing has always worked fine for us (family of 7 then,

3 now).The only thing I&#39;d want different is the auto lighter- piezo or "the little turbine" (Bosch), because of the gas- but the unit is on the wall next to the toilet (in NW earthquake country- 2 shakes, no problems), so it probably heats that space- a little.

We do have a small place- around 1000sq&#39;- and the space for a tank is also an issue. When we heated and cooked with wood, I had a tank that ran through the woodstove... and took all insulation off of it- using it as a radiator, as well as a hot water tank. That setup, w/ a solar water panel, would be my favored Luddite fallback mode...

Amen to that... I&#39;d favor going to radiant floor heating, if the house is situated to take advantage of that... and, if I lived in horse &#39;n dairy country, I&#39;d go for the 250 sq&#39; slab with pipes embedded, on the downwind side of the house, upon which manure is piled, to fire the heat exchanger in my own slab flooring... ^..^