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Kohler DTV (Digital Thermostatic Valve)

Posted by giuseppe_paolo (My Page) on
Tue, Mar 29, 11 at 1:15

Have the DTV valve and using all 6 ports with copper piping to 8 body sprays (2 per valve), a main shower head, and a handheld shower head via wall supply elbow.

Then a 2nd handheld shower head also on a slide bar and volume control wall supply elbow, operted by a manual rough in valve and thermostatic handle trim for backup if dtv ever not workign.

Just have the plumbing done and need to have it all tiled over and digital interface installed to experience it.

Have access panel to the valve in the master bedroom behind master bath. And yes I know its going to be loud.

any experiences with or ppl who have DTV and DTV2 setups, plus pics are always fun.

I have 4 Hansa off the wall body sprays up front and then 4 round kohler water tiles on the sides 2 on each side)

I know the valve can handle it all, i just hope the house water pressure can give adequte pressure to the 21gpm digital valve to run all 8 body sprays and at least one of the 3 shower heads at a time.

Also concerned how quick hot water will run out with I believe an 80 gallon water heater (will have to check but i'm pretty sure its bigger then our townhouse 50 gallon one was I think). May have to look into tankless water heater but i know its expensive.

Already know that no way will someone be able to shower for any longer period of time with body sprays and be abale to fill the larger corner air tub any time soon before or after that.

All discussion on body sprays, and especially Kohler DTV welcome. As well as tankless water heater. Is it going to be a must? which ones are good and what is involved? Does it work with existing traditional water heater or will that have to removed? that would be a shame as its only 5 years old.


Follow-Up Postings:

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RE: Kohler DTV (Digital Thermostatic Valve)

The "car wash" shower ? You are certainly going to need more hot water capacity if you want to shower more than 6-7 minutes with that config.- and FORGET ABOUT anyone using hot water anywhere during or after that 7 min. shower.

"May have to look into tankless water heater but i know its expensive. "

- Seriously ??? You just bought a $3000 + shower valve and you are going to squeak about a heater now? Kinda like buying a Ferrari and complaining gas costs $4/gal to run it.

Talk with your plumber , but we've found a hybrid system works best. Feed the 80 gal with a tankless. The top 3 are Noritz, Takagi, and Rinnai for gas units. They will need a lot of gas to run -so be sure your piping can handle it.


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RE: Kohler DTV (Digital Thermostatic Valve)

your sarcasm and attitude I could do without but appreciate where you tried to actually help.

the digital shower valve was $690 not $3000 but yeah I see your point. If you do something, you have to be willing and able to do it right.

I think its an 80 gal water heater and being able to still use that in cojunction with a tankless that feeds (hybrid) sounds good.

Thanks for the recommend of the top 3 thankless.

edit: just talkied to my plumber and he can do it, but told me they are like 3k. so why the digital valve wasn't even close to that, your # was right for the tankless, yikes.

I guess will be worth it and even neccesary though and my gas lines are good so install should be mostly ok. Plumber mentioned having it feed the master bath (for shower with body sprays and the air bath) directly.

Would that be better then having it feed the 80 gallon tankless. He seemed to say that directly feeding the bathroom would ensure you dont run out of hot water.

Oh and he said though expensive, you make up for it within a year even I think he said on your bill (water I guess).


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RE: Kohler DTV (Digital Thermostatic Valve)

1. What sarcasm? - I tell it like it is, it may not be in a nice bow wrapped package, but it's factual, accurate and based on years of experience and free. If you don't like like the delivery, you can get lost, hire a designer on your own nickel, or wait around and hope someone else has any idea about your setup.

2. List on the DTV is $1250 with a street price of around $800 and controllers are $140o-1500 with a street price of $900-$1000 + the cost of your 8 sprays @ what $100 a piece + the 2 shower heads at $$$ ea?

You've got close to 3 grand in hardware costs in that shower. I suppose I should have left off "valve" for absolute clarification. SO... let's say you got a super Crazy Eddie's, Xmas in July, closeout special, today only price on all this gear - you still will have $ 2 grand in it and my point about complaining about filling up the tank is still apropos.

3. Your plumber is not so good in math and economics. There is no way a tankless will pay for itself in a year even if your rates are sky high- 5 years maybe - but 10 is more realistic.

4. If you go all tankless you are going to need at least 2 units that will flow 8-10 gallons a minute. These will use approx. 400,000 BTU's and that's a SERIOUS amount of gas and I'm willing to bet your system was not designed for that kind of add on. So, factor that cost in to the equation. This 400k is in addition to your other demands like cooktops, dryers, BBQ's , fireplaces, generators, and HVAC plants.

This would be the same if you feed the bathroom directly or not. Your shower needs approx. 15 GPM to feed it and that's a lot of hot water no matter how you produce it.

5. You might get by with with one tankless in a hybrid arrangement, but you'd better have some one that knows what they are doing spec it out. Guessing on the jobsite is not the way to do it.

6. You might also use super heated water in the 80 gallon and a mixing or tempering valve to boost the amount of hot water available for domestic needs.

Take away - if you run the shower the way you state above you need to be able to get 14 -15 gallons of hot water to that valve for as long as you want to run it. An 80gal tank affords you about 7 minutes, assuming the tank was full when you start and no one turns on the washing machine, dishwasher, uses another shower or uses hot water to wash their hands.


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RE: Kohler DTV (Digital Thermostatic Valve)

2 tankless water heaters? Yikes.

My contractor does everything and did a good job with the piping and said tankless is no problem buf if doing a hybrid setup is complex I worry that because he does everything, he may not be expert at plumbing to do a hybrid setup.

He mentioned having the tankless just feed the masterbath as thats the only place that needs it and the rest of the house would be fine on the 80 gallon.

If feeding just the master bath with the tankless, do I really need 2? Or can I get away with one.

Btw, I got the interface for $620. Hopefully I can find a tankless or 2 (if neccesary) for similar 50% off deal...


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RE: Kohler DTV (Digital Thermostatic Valve)

"He mentioned having the tankless just feed the masterbath as thats the only place that needs it and the rest of the house would be fine on the 80 gallon.

If feeding just the master bath with the tankless, do I really need 2? Or can I get away with one. "

You can do anything you want but.......................

Like I said, your shower alone will use about 15 GALLONS A MINUTE - more if you run both shower heads with the sprays at the same time. This is the amount of water you have to supply the DTV in order to run the thing - remember it's rated at 21 GPM !

Now, you can use your 80 gal tank or a 50 gal tank or whatever size, but you'll only be able to shower as long as there is enough hot water in it - remember the shower is going to empty it at 15 GALLONS A MINUTE. ( actually a bit less than that as some cold water will be used by the valve)

SO- we are back to a time limit on that shower with multiply 'features" running. In your case around 6 to 7 minutes with the 80 gallon tank.

"If feeding just the master bath with the tankless, do I really need 2? Or can I get away with one. " ???

This is one way to do it, but remember - you still need 15 GALLONS A MINUTE of hot water output. Take a look at co.s offerings and you'll see that none have a heater that delivers more than about 14 GPMs - and that is with an ideal 45 degree rise in temp. If you live in a cold climate where the water temp is lower than 55 deg. that rating in GPM will go down significantly. For example - Takagi has a unit that does 14.5 GPM with a 45 deg. rise. It will do that easily in Florida, but that same unit installed in Maine or Colorado will only pump out about 7- 9 GPM ! SO......................yes, I'm pretty confident you will need two tankless units to feed your shower/house. This is almost always a better arrangement as during times of less demand only one unit will be running anyway, and those 12-15 GPM units are very very expensive! The drawbacks of two units are you'll need more wall space and you'll have twice the venting and gas supplies to run. One advantage with 2 smaller units can be teh use of PVC vent pipe. Those monster 14 GPM units almost always use stainless steel vents, while many of the medium/large units can use PVC pipe to vent. This is a huge $$$ consideration especially if you have a long vent run.

You will also need to consider how that bath's pipes will be isolated from the rest of the house if you go with a bath only setup. Pretty easy if you have PEX system with a matrix panel, more complex and more $$$ if its a copper branch system.

ReCap: you have to produce a LOT of hot water to feed this shower and doing so will usually not be done on the cheap and I don't see a way to make enough volume with one tankless by itself.

Also in case it wasn't clear before your gas system and piping are going to have to support at least 400,000 btu at the install point of the tankless heater(s) IN ADDITION to providing the needs of your other gas appliances. Be sure you sort this before you go further - otherwise you will be in the same boat you are now with the shower - you'll have a high need and your system won't have adequate supply.


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RE: Kohler DTV (Digital Thermostatic Valve)

Interesting points you make here albeit with a bit of a chip on your shoulder for some reason.

Thanks for trying to help if that was in fact your intention...

I will check with a professional plumber to verify all of this.


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RE: tankless water heater)

But so far already some of it was deemed inaccurate


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RE: Kohler DTV (Digital Thermostatic Valve)

you may well need a pressure increasing pump system. will be installing this setup in about 3 weeks --and will report back.


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RE: Kohler DTV (Digital Thermostatic Valve)

Doesnt the digitsl vslve tske the waterpressure you hve and out out 21gpm?

If you do need some presure increasing pump where does thst hsve to be connected to? Csn it be added sfter everything is tiled up.

Plumber did a pressure test but only to test for lesks i think not measure waterpressure when most or all 6 ports on.

Hopefully if this is needed it csn be added without much trouble

Already have tile backerboard up covering pipes.

I imagine it would have to come before the hot snd cold inlets feeding the digitsl vslve? But coukdnt put it in basement where main water feed is as then tht might increase the water pressure too much for rest of house thst doesnt need it?


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RE: Kohler DTV (Digital Thermostatic Valve)

Garden web needs an edit button l(like all kther forum ps have) badly. Thst snd i need to stop rush typing on phones and tsblets with crappy keyboard.


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RE: Kohler DTV (Digital Thermostatic Valve)

hello giuseppe_paolo , I read your first post and will respond to it.

here are your answers.

your description is clear and you understand the situation. Some people take long showers (or they take tank-draining showers) and they are bothered by having no more hot water for while. That is not you, because "your description is clear and you understand the situation." Some people have one person living in their house who drains the tank, and they are bothered by having no more hot water for while. That is not you, because...

Your current water heater is what it is, and it's fine. Fine, because you "understand the situation" and are prepared to live with not expecting to have more hot water after a long shower (or after a tank-draining shower). Whew. Hope this is clear.

The only real question that I see here is whether or not it can be justifiable to have a secondary tank (or tankless heater). A plumbing forum inhabited by plumbers might help you get a range of answers. E.g. http://www.terrylove.com/forums/index.php .

You wrote out a lot, and it shows you know what you are doing. I confirm you know what is what, which way is up, right from left, and so on.

80 gallons is what it is. If I call it big enough, that is my opinion. Some people want to stay for an hour or two in a hot mist shower while making babies or the equivalent, and they would need more hot water.


Everyone has their own style. You are correct that antss has a style, borderline accusatory in tone, that can upset the reader. My style upsets other readers for other reasons. Oh well... Regardless of how it may be perceived, I hereby confirm to you by the powers vested in me that you are going to be fine with your current tank and that you can choose what to do next AFTER you start taking showers; you can wait to decide.

Hth


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RE: Kohler DTV (Digital Thermostatic Valve)

"But so far already some of it was deemed inaccurate"

which parts ? and by whom ?

"Doesn't the digital vslve tske the water pressure you have and out out 21gpm? "

No, it is CAPABLE of flowing 21 GPMs maximum if you supply it with enough water and pressure. It does not increase pressure or volume. If you only have 30 PSI of pressure- it won't flow 21 GPM. If you feed it with 1/2" pipes - it won't flow 21 GPM. Basically it's 3/4" piping with 40 or 45 PSI (I can't remember offhand) to be able to feed this valve adequately.

Look - I've told you you may not like my writing style, but I've designed and installed a half dozen of these or more and they all work fine, first time out, with no going back to add pumps or pipes or heaters or whatever. So, I know what I'm talking about, but this is not the ONLY way to provide hot water for this thing. The mere fact that you are asking here about any of this tells me that you and you plumber don't really have a good handle on using this valve or at the least you don't have confidence in your plumber.

Don't like my advice or my delivery? Bugger off to another forum, or don't read it, or do the opposite, or just go with your plumber's rec. and hope it works satisfactorily, or hire a designer in your town, but for gosh sakes - quit moaning about it - NO ONE LIKES A WHINER !


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RE: Kohler DTV (Digital Thermostatic Valve)

Davidro1,

Hehe, thanks, and I like your "style".

The 80 gallon could be mostly fine but most setups have 4 body sprays not 8 and also with air bath, I feel we will need backup if we ever wabt to take bath & shower back to back. Plus kids baths etc.

My gc who does plumbing may not be the ultimate expert in plumbing but is probably better then most avg. Plumbers and may not be up on everything buy hes pretty smart and accurate.

He was good enoigj to do a maze of copper piping snd loops for the dtv with 8 body sprays, a shower head and hand held plus still room to do a manual controles roughin valve piped to another wall supply elbow (as a back up if dtv ever down)

I like a lot of ppl on these forums started small and ended uo doing mlre then i intended. I woukd have been fine with 4 body sprays but couldnt cancel/return the 4 off wall sprays and really wabted the kohker water tiles because they are flush so also got 4 of those for the sides.

The bathroom project has been a nightmare because of a bad middleman contractor who held money & matetials plus made mistakes aming other probkems and huge delays.

I just want to get done and resume my life with my family.

Its just if this is our forever house, my wife said if you are going to do it, donit right. I told her no to body sprays and now end up with 8. The kohler dtv was also not intended but I went with it to save ne from buying more valves and trims to control everything and i got good price on the valve and interface.

Of course the space in wall was tight so couldnt use the more expensive pex so had to use copper which while cheaper tool my gc/plumber 4 days ti do paid by the hour.

Anyway, he said his friend did a tankless, that its great and he can install no problem. He suggests having it feed just the master bath and will be plenty. I think my gas lines will be sufficient cus they areinly 5 yrs old and pretty thick yellow pvc gas lines. No idea where hed install it and how it would tie into just the bathroom but if it works out and the bathroom ever gets done and all wotks ok will be a miracle at this point.

Gas lines are in basement under the side of the house where masterbathroom is and water softener (we brought with us from old house) and water shutoff is on the other side of the basement under side of the house my daughters bathroom is which is probably why hers has the best water pressure.

So hopefully 1 medium/large tankless for just master bath will be enough. Still have to pick and find one.

As for water pressure, ive been worried about that from the start. We dont need or neccesary love super high water pressure but as long as we have volume control (which dtv does and even the manual handheld i put on a supply elbiw with vc) then its good to have the power available. And bodysprays are useless if the water just trickles out (ive seen bad installs)

I guess i just hoped the dtv would magically boost the water pressure.
But I fear a pressure booster might be neccesary but I have no clue where ti get one or how its installed. I fear it would have already had to be put in with the pipong which now has tile backerboard sheet rock covering it all.

Maybe the lressure booster can be put in basement with the tankless, both feeding just the master bath?

I also have the major stress of getting a new tub last minute now that my order was canceled by the manufac believe it or not due to a most ridiculous and border line illegal debacle of which we wefe the victim of (see Jason hydrotherapy thread)

And depending what tub we get, may need to put an access panel in the laundry room ceiling below tub to access a second and left sided blower.

It never ends, the expense and the stress that is. Add to that a scammings middleman contractor who currently has our money and some materials but hasnt even used our money to get the rest of the tiles yet.

Oh and because of him owing the gra ite fabricator money we had tonuse a different fabricator for the seconf half of the stone for the jov so its not going to match.

Anyway, we'll keep this thread about Kohler dtv and the water heater and water pressure pump needs therein.


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RE: Kohler DTV (Digital Thermostatic Valve)

based on current use especially with the water pressure being on the lower side on the upstairs side of the house the master bath is in, I am figuring on needing a tankless water heater and some type of pump to increase water pressure.

I think both will be somewhat to very needed and I figure better safe then sorry to have enough hot water and water pressure.

I am leaning towards a Takagi tankless water heater but which one?

The T-K3 or the T-H2?
http://www.takagi.com/index.php?p=products.php&page_id=2&category_id=1
The T-H2 gives more gpm so thats probably the one to go with between those 2 Takagi models.

or maybe twin Rinnai R75LSi units? I may likely need 2 though not sure if I'd need 2 with the Takagi?

as for the pressure pump, I don't even know where to start. but again, I already know its going to be low even with 4 body sprays and a shower head, let alone 8 body sprays and 2 shower heads. the DTV lets you control the volume of each spray I believe, so could always turn down the volume if hte pressure is too high which seems likea good problem to have.


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RE: Kohler DTV (Digital Thermostatic Valve)

What do you guys think of the Pentair Water 3075SS Pressure Water Booster System 3/4 HP 115-Volt

seems like what I need and has some good reviews on Amazon and the like.

I mostly only need it for the master bath not the whole house. In fact one bathroom the pressure is kind of medium low but we like it that way in there and the valve is not a volume control type so we worry if its too hight we can turn it down.

seems like that pump is made to feed the whole house but I guess it could be made to feed just the master bath.

Everywhere else mostly has volume control so we could just look into a way to add volume control to the one bathroom shower without changing the rough in valve and trim.

but the tankless (i'm hoping 1 is enough) I would have feed just the master bath.


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RE: Kohler DTV (Digital Thermostatic Valve)

Did you get the dtv system finished? Impressions?


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RE: Kohler DTV (Digital Thermostatic Valve)

Thinking about your tankless heater question. I have a Triangle Tube Smart Water with a 75 gallon capacity, indirect - fired off my oil boiler. I'm thinking to feed a DTV, with 4 outlets - a hand shower, a 4-tile rain head, 3 body sprays, and a wall head. I have considered putting in a second 75 gallon Smart Water, which I can easily do. I'm plumbing the bath with 1" on both the hot and cold side - taking 3/4" off that for the DTV. The hot water will be continuously circulating. I'm also putting in an MTI air tub.

Your shower is likely bigger than mine (76 x 42). FYI, I am deciding whether to fill the Tub using 2 ports of the DTV (via a virtual spout) - or whether I will dedicate all 6 ports to the shower. BTW, I am not very happy about Kohler not having a portable control like Moen. Also, think about this. For the price of one Kohler control, you can buy a fully loaded iPad which is 10 million times more intelligent - so I think Kohler is pretty stone-age in its electronic strategy (the DTV is 5+ years old) - and has no interfaces to home automation. All its interfaces are wireline and proprietary. For these reasons I may go with the Moen IO Digital. Still deciding...


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RE: Kohler DTV (Digital Thermostatic Valve)

ping these folks. http://www.aquascience.net/

They'll walk you through whole house pumps and filters. A high-end / high capacity booster set-up (variable speed) ran about $1,600 all-in. I bought a whole house filter from them.

Hope this helps!


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