# tankless/on demand



## d-rez (May 16, 2007)

I have a HO who is requesting a tankless for their project. I would like some advise on which is/are the best brands made. Two bath, kitchen, laundry. Gas. Thanks, Chris


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## KillerToiletSpider (May 27, 2007)

I have used Takagi for residential as well as light commercial applications with no problems, in fact I installed one in my sisters house.


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## mdshunk (Mar 13, 2005)

I see mostly the Rinnai brand in my area. http://www.foreverhotwater.com/ Takagi is another popular brand.

As with all high-tech appurtenances, I think it's very important to buy local so that you can source your repair parts locally. I don't think your local real plumbing supply house is going to sell you any junk.


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## Kent Whitten (Mar 24, 2006)

I picked up a Bosch at (cough) Home Depot and it works great. Only problem I really have with it is not having a constant consistent hot water temperature which I am guessing it has something to do with my water pressure not being regulated.


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## KillerToiletSpider (May 27, 2007)

framerman said:


> I picked up a Bosch at (cough) Home Depot and it works great. Only problem I really have with it is not having a constant consistent hot water temperature which I am guessing it has something to do with my water pressure not being regulated.


Probably not, I have never seen one of those Bosch tankless heaters work correctly.


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## Chris Johnson (Apr 19, 2007)

I had an Aquastar about 10 years ago, I think they are now Bosch, it was horrible, the house I am in now I put a Rinnai and it works pretty darn good, the only advice I can give is don't use a manifold system, eliminates having to get out of the shower and run the hot water again for a while to start shaving in the sink, keep the runs as direct and as short as possible. 

Also make sure you adequately size the gas line these puppies are running 150,000 BTU's per hour plus, this can definitely impact the correct use of the system, I have seen a few where the HW tank was removed and Tankless installed and connected with the old 1/2" line which proved to be the problem.


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## JamesNLA (Jun 2, 2006)

I have written up several long posts on tankless as I have a lot of experience. I am in the process of doing a write up with pictures of not only one of my more recent installs, but a new recirculation system that has got me excited about the results. Stay tuned for that post, I need to go to Costco today and get more beer!!


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## skyhook (Mar 17, 2007)

JamesNLA said:


> I have written up several long posts on tankless as I have a lot of experience. I am in the process of doing a write up with pictures of not only one of my more recent installs, but a new recirculation system that has got me excited about the results. Stay tuned for that post, I need to go to Costco today and get more beer!!


I for one will be watching. :thumbsup:


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## Ron The Plumber (Oct 10, 2006)

JamesNLA said:


> I need to go to Costco today and get more beer!!


 Yea , Beer :thumbsup:


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## Rich Turley (Apr 9, 2005)

I have only installed Rinnai, but like them. Keep in mind that "tankless" and "on demand" are not the same thing.

Rich


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## ChrWright (Jul 17, 2007)

I recently had a Bosch 250sx installed at one of my projects that delivers great hot water.....Unfortunately it suffers from intermitent "no flame ionization detected with waterflow" problem we're still trying to troubleshoot...


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## mdshunk (Mar 13, 2005)

ChrWright said:


> I recently had a Bosch 250sx installed at one of my projects that delivers great hot water.....Unfortunately it suffers from intermitent "no flame ionization detected with waterflow" problem we're still trying to troubleshoot...


Clean the flame sensor or replace the flame sensor. This crops in damp basements or units installed in laundry areas.


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## ChrWright (Jul 17, 2007)

That's my next step. 

The unit is in a closet on the 2nd floor, however. It did take some water initially through the intake ducting (poorly installed intake boot on the roof). I'm guessing that's a contributing factor/cause of the problem.


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## KillerToiletSpider (May 27, 2007)

ChrWright said:


> I recently had a Bosch 250sx installed at one of my projects that delivers great hot water.....Unfortunately it suffers from intermitent "no flame ionization detected with waterflow" problem we're still trying to troubleshoot...



Rip it out and replace it with a decent unit, the Bosch is a terrible unit.


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## ChrWright (Jul 17, 2007)

How many Bosch units have you worked with? Direct experience or anecdotal?


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## KillerToiletSpider (May 27, 2007)

ChrWright said:


> How many Bosch units have you worked with? Direct experience or anecdotal?


I used to work for a service company that was the authorized repair company for Bosch, about 50% of all units sold by Home Despair require service in the first four months, almost all of them for component failures.


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## ChrWright (Jul 17, 2007)

How nice...

Good to know for future projects, though. Thanks.


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## Kent Whitten (Mar 24, 2006)

makes me oh so much better having a bosch LOL. It's probably a POS, it delivers for now. I'll try the cleaning the sensor thingy....someday


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## KillerToiletSpider (May 27, 2007)

framerman said:


> makes me oh so much better having a bosch LOL. It's probably a POS, it delivers for now. I'll try the cleaning the sensor thingy....someday


It is a POS, when it dies, and it will, replace it with a good one.

Home Despair has a pretty good niche in this area, not many suppliers carry tankless heaters, there is not a single supply house near me that stocks them, and the only ones I can get through them are Rheem or Takagi. Rheem is a piece of garbage, similar to Bosch, but they are half the price of Takagi, in the long run you get what you pay for.


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## Grumpyplumber (May 6, 2007)

*Rinnai, Takagi, Paloma/Rheem (same unit) are reliable as far as performance, as long as You DON'T use anything less than a "whole home" unit.*
*The newer models come with flow restrictors that will slow the hot flow if the unit can't keep the set temperature.*
*I've installed one Bosch and that was that last one I'll ever install, I sat here reading this thread with a smirk...good to know it isn't just me, those units SUCK.*


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## irate808 (Sep 17, 2007)

Ive installed a couple Bosh's before, and thankfully I have not had a problem yet. I mostly install Rinnai's. They seem to work very well. I recommend them to all my customers, just because Ive heard bad stuff about the Bosh's(even though I have not had any problems with it so far.)


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## Joasis (Mar 28, 2006)

Just curious, but has anyone installed any electric units that are worthwhile yet?


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## KillerToiletSpider (May 27, 2007)

joasis said:


> Just curious, but has anyone installed any electric units that are worthwhile yet?


Worthwhile for a single bathroom or an entire home?


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## Joasis (Mar 28, 2006)

Whole home water heat?


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## KillerToiletSpider (May 27, 2007)

joasis said:


> Whole home water heat?


I have yet to see one.

Based on what I know from the on demand type, one that would serve a whole house would make the electric meter spin so fast you could slice meat with it.


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## Joasis (Mar 28, 2006)

We did an office remodel 4 or 5 years ago, and the plumbing contractor installed one....I do not remember the brand, but the water never got over about 110 degrees...and it was supposed to be a whole home unit....


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## Grumpyplumber (May 6, 2007)

*Good timing.*
*I'm currently looking into a customer request for one, so far it seems like SETS is about as good as they get, but feel free to correct that.*
*Regular electrics only have a 15 GPH recovery so swapping to a smaller tank is chancey.*
*the customer has a 50 gal and only two in the house, lotsa math on this baby.*


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## JamesNLA (Jun 2, 2006)

Huh? Ya know I thought I was simply misreading what you all were talking about....."whole home". Grumpy...lots of math? This makes no sense to me. Just count the hot water fixtures and you 3/4 done figuring out which unit to use. 2 people......either a 7.5 GPM or a 9.3GPM will due just fine.

.....wait, ur talking electric....my bad!! 
If you want to know the best GAS tankless, here it is: http://www.tanklessisgreen.com/

Still working on my write up that will teach you old farts the new stuff. But just like the old timers in line at the supply house "I don't like them things". 
I asked why, "because it's too much work to install". LOL...Ok, I'll do them all then! I like giving them a hard time about this. The pros V cons on a tankless setup is quickly gaining attention and starting to become a "norm" of sorts.


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## KillerToiletSpider (May 27, 2007)

JamesNLA said:


> Huh? Ya know I thought I was simply misreading what you all were talking about....."whole home". Grumpy...lots of math? This makes no sense to me. Just count the hot water fixtures and you 3/4 done figuring out which unit to use. 2 people......either a 7.5 GPM or a 9.3GPM will due just fine.
> 
> .....wait, ur talking electric....my bad!!
> If you want to know the best GAS tankless, here it is: http://www.tanklessisgreen.com/
> ...


I install a few tankless heaters, and the trend is growing, the condo work we do and the architects and designers we deal with don't want to give any condo the space to install a tank type heater. I have never dealt with Noritz, but I have been very happy with the Takagi's we have been installing, I recently did a bar/restaurant where we installed four Takagi Mobious 1 units in series, and they never run out of hot water. I will be installing a tankless in my house when my 27 year old Rheem 40 gal finally bites the dust, with a Takagi.


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## JamesNLA (Jun 2, 2006)

> installing a tankless in my house when my 27 year old Rheem 40 gal finally bites the dust, with a Takagi.


If you decide to REALLY get into it with all the tankless stuff and you learn the Noritz systems, one thing you'll learn is that they license out their technology to a few compeditors. Takagi leases the most, their tankless units are the most similar than all others out on the market. I do like the Takagis', but hate the rest. Rannai is popular, but it is best compared to a Chevy Malibu, verses a Takagi - being a Lexus - and a Noritz - like a high end BMW. 

As for that 4 unit setup in series? If it was in series and there was 4, that would be an extremely high demand of volume of water to be heated.
If it was in parallel the demand of large piping hot lines would best be met in this application. And also redundency. I have installed 3 side by sides when I only needed 2 for the size up, but if one of them fails, and the kitchen can't keep the dishes clean, the health department can and will shut them down...mid shift. The loss a business can take, is not worth it to them, so install a 3rd fro redundency. With the Noritz line, there is one remote for all 3. A data cable interconnects - every 24 hrs it shifts the main usage loads to the other heater, therefor all have equal wear and tear. It's a cool feature, sometimes helps with the sale. I'll try to get that write up done sooner rather than later. Wanted to make it all nice which means it's a lot of work, therefore after working all day, I don't wanna work any more, but I will get to it. There is some really cool stuff going on in the tankless world!


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## Grumpyplumber (May 6, 2007)

*Killer, exactly.*
*It's unavoidable, I've done maybe a dozen in the last year, all gas.*
*The calls come in for them, whether I want them or not.*
*You either try to convince customers they suck, or wake up and get over fear of new fixtures.*

*James ya lugnut!*
*I KNOW how to size the damn things in terms of GPM.*
*The "math" I'm talking is figuring the benefits of an ELECTRIC tankless.*

*Figuring out standby heat loss is about the only factor to consider in adding up potential savings.*
*It means having to figure the heat loss per sq foot of surface area on a given tank size, converting BTU's to watts, then adding that per hour for a rough idea of energy costs for it to sit there.*

*As you obviously know, electric tanks generate about 15gph & use 9000 watt while on (for double element 240 volt).*
*The math, as you know, is VERY simple...with a watt equalling 3.414 BTU.*
*The heat loss part adds up to close to nothing from what I can see with about 15BTU per sq foot of surface area and , with the math being so simple to find the surface area on a 50 gal tank.*
*Being that a gallon accounts for 7.5 cubic feet and then it's all a cakewalk with finding the cube root, multiplying by 6 and VOILA!*
*Simple math.*
*Whats my answer?*


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## KillerToiletSpider (May 27, 2007)

JamesNLA said:


> If you decide to REALLY get into it with all the tankless stuff and you learn the Noritz systems, one thing you'll learn is that they license out their technology to a few compeditors. Takagi leases the most, their tankless units are the most similar than all others out on the market. I do like the Takagis', but hate the rest. Rannai is popular, but it is best compared to a Chevy Malibu, verses a Takagi - being a Lexus - and a Noritz - like a high end BMW.
> 
> As for that 4 unit setup in series? If it was in series and there was 4, that would be an extremely high demand of volume of water to be heated.
> If it was in parallel the demand of large piping hot lines would best be met in this application. And also redundency. I have installed 3 side by sides when I only needed 2 for the size up, but if one of them fails, and the kitchen can't keep the dishes clean, the health department can and will shut them down...mid shift. The loss a business can take, is not worth it to them, so install a 3rd fro redundency. With the Noritz line, there is one remote for all 3. A data cable interconnects - every 24 hrs it shifts the main usage loads to the other heater, therefor all have equal wear and tear. It's a cool feature, sometimes helps with the sale. I'll try to get that write up done sooner rather than later. Wanted to make it all nice which means it's a lot of work, therefore after working all day, I don't wanna work any more, but I will get to it. There is some really cool stuff going on in the tankless world!


That restaurant has two kitchens, and four commercial dishwashers, as well as a glass washing station and four public bathrooms, we sized it for everything running at the same time, with the Takagi rep.


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