(206) 949-5683, Top Rated Plumber, Seattle
Page 13 of 14 FirstFirst ... 34567891011121314 LastLast
Results 181 to 195 of 202

Thread: My Tankless Experiment

  1. #181
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,382

    Default

    You've got 10 more degrees to match my worst case temps last year - it hit 33 degrees incoming. Under those conditions, I think a tankless would not keep up. The things are generally designed around 50-degree, worst case, incoming water; you're already below that, and it tends to be worst around the end of Feb (at least here).
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  2. #182
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking This guy has got me beat already

    Just when you think you have seen it all

    Whole looking for pics of water heaters for this years yellow page add, I stumble on this tankless information....

    he has me beat hands down.....
    and has in my opinion
    gone off the deep end...at around 7 grand here.......

    but their is a lot of very valuable information....

    http://www.mattox.com/water_heaters/index.html


    check out the two Rennai tankless heaters he installed

    and the two electric heaters..

    he certainly has me beat.....

  3. #183

    Default Tank vs Tankless cost calculator (mattox)

    That mattox site that you linked to has a really easy to use calculator. Basically, the colder your incoming water and the more usage (more people in the house etc...) the shorter the payback period for a tankless (except there is no field for higher tankless maintenance costs).

    Myself, I requested an estimate on a Rinnai on Friday. It has an energy factor of .84 One tanked HWH I saw had an energy factor of .63

    I am considering the AO Smith Vertex because the manufacturer says it could be simultaneously used hot water and for space heating (like radiators). I am thinking about moving my washer/dryer to the currently unheated garage and make the utility room (heated by existing furnace) into a second bathroom.

    One web document mentioned the department of energy testing procedure uses hot water "draws" that aren't like real world usage. It will be interesting to see how this thread's poster does with his experiment (more realistic).

    I agree with the plumber who said "one product is not for everyone". Customers that neglect maintenance will always pay more, no matter what product they have.

  4. #184
    Retired Defense Industry Engineer jadnashua's Avatar
    Join Date
    Sep 2004
    Location
    New England
    Posts
    21,382

    Default

    My boiler runs at a minimum of .94 and heats my indirect WH tank...

    Personally, I don't see how a tankless would pay for itself faster if the incoming water is colder...the maximum temperature output just drops along with the input once it reaches its limits. It takes the same amount of heat to raise x gallons y degrees, whether it is being done in advance or in-line. Obviously, the efficiency of the heat delivery will affect the total costs. There are tank type heaters that are quite efficient.

    Most tankless can only produce their maximum rating and flow with incoming water at around 50-degrees. Many places of the northern US have water approaching freezing for part of the winter...this has one of two results on a tankless: either an unacceptablly low output temperature or a severely limited volume. Neither of those issues occur with a tank type heater. Some may put up with that low flow, but those who use hot to fill a big tub, or for certain loads of clothing in the washer just may not want to put up with the limitations or the costs to provide the desired flow.

    Even with that difference in efficiency, countering with the difference in purchase and installation costs, it would take quite a number of years for the typical user to come out ahead.
    Jim DeBruycker
    Important note - I'm not a pro
    Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014

  5. #185
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking my summer tankless experiment




    yes that is 3/4 inch toung and groove real cherry panelling on the walls from 1966

    well the summer floods came about a month ago and put about 6 inches of water in our downstairs walk out home

    my heater never flooded out but the gas meter for my tankless experiment
    did get half submerged.... it was a sealed meter and still seems to be chugging along...

    the only good thing about it ,
    is I got good flood insurance


    of course this little set back will not deter me in my endeavor to
    prove which heater is more economical

  6. #186

    Default Re: My Tankless Experiment

    This may have already been mentioned, but I didn't have a chance to read every
    post in the thread. When I looked into the tankless, I rejected it for a few reasons:

    1. The "whole house" units don't click on until 0.5-0.75 gpm. So hot water to
    a lav can be a problem.

    2. If the power suddenly goes out, the water turns instantly cold once the
    supply line to your shower is used up. This also applies to the gas units
    with the electronic controllers (all the good ones as far as I can tell)

    3. Theres no reserve for serges. So Even with the Takagi flash T-H1 @199KBTU/Hr
    and 95% efficiency, I could bearly run two showers here over 7100 ft elevation,
    and any intermittent (washing machine, dishwasher, lav...) use during the two
    simultaneous showers would drop the temperature of the showers.

    I looked into combining the Takagi with a small tank to eliminate most of the
    above problems, but instead of all that mickey mousing around, I just went
    ahead and bought a 199KBTU/Hr Polaris (high efficiency, 50 gallon, urethane
    insulation).

    Dave

  7. #187
    Plumber Cass's Avatar
    Join Date
    Nov 2005
    Location
    Ohio
    Posts
    5,984

    Default

    Quote Originally Posted by master plumber mark View Post



    yes that is 3/4 inch toung and groove real cherry panelling on the walls from 1966

    well the summer floods came about a month ago and put about 6 inches of water in our downstairs walk out home

    my heater never flooded out but the gas meter for my tankless experiment
    did get half submerged.... it was a sealed meter and still seems to be chugging along...

    the only good thing about it ,
    is I got good flood insurance


    of course this little set back will not deter me in my endeavor to
    prove which heater is more economical


    May I suggest a Zoeller Aquanot 2 battery back up sump pump.

  8. #188
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking and pump it where????

    Cass....now thats a cute idea.....



    basically the home is a walk out bi- level on the creek.
    and the water came into the home from 3 sides.........

    the home should have been built about 3 feet higher

    I am considering putting up a burm or pour a wall perhaps about 5 feet out and then install a pit out on the patio to
    pump the water back over the wall....


    this is the second time it has flooded , once in 66...

    so do you just gamble on it or not????




  9. #189
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking sounds like you had one

    Quote Originally Posted by dave148 View Post


    I looked into combining the Takagi with a small tank to eliminate most of the
    above problems, but instead of all that mickey mousing around, I just went
    ahead and bought a 199KBTU/Hr Polaris (high efficiency, 50 gallon, urethane
    insulation).

    Dave


    sounds like you already fought the battle of the bulge with a tankless and had nothing but troubles...


    any other experineces you care to share??

  10. #190

    Default Re: Tankless

    >sounds like you already fought the battle of the bulge with a tankless and had nothing >but troubles...


    >any other experineces you care to share??

    All battles were on paper. Fortunately I figured out what the problems would be
    before I made a purchase.

    However, here is one calculation you might be interested in: The claimed financial
    advantage in a tankless over a tank system is standby loss. Using the 1% per hour
    specification of the Polaris, the standby loss should be:

    50 gallons * 8lb/gal*60 degF / 858 (btu/ft^3)*(0.01 loss)*$.0073 = 0.00160/hr
    = 4 cents/day

    This is using the price for gas, and the density of gas here in Colorado Springs.

    Now maybe we shouldn't believe American's numbers for the Polaris, so let's
    check that estimate against the envelope loss on a cylinder the size of the
    heater with 2" urethane insulation:

    Assuming R-value of 12 F ft^2 hr/BTU (2" of urethane):
    Surface area of 22" diameter x 68" (??) tall cylinder:
    3.14*22*68+2*3.14(11)^2 = 3385 in^2 /144= 23.5 ft^2

    If 60 degrees across insulation,
    23.5 ft^2 /(12 F ft^2 hr/BTU) = 2 BTU/HR

    Current Cost of gas $0.0073/ft^3
    $0.0073/ft^3 * (ft^3/858 btu at 7000') =$8.51E-6/btu
    * 2 BTU/HR *24 Hr/Day =$408.4 E-6/day = $0.0004/day

    Maybe 2" of urethane was too agressive. If the R value of the insulation
    is reduced to only 2, the envelope loss is still only 2.5 cents/day!

    Since the Polaris spec gave 4 cents/day, I'll assume most of the heat loss
    is actually through the hot pipe, and not through most of the cylinder
    area.

    So using the worst number we came up with above, we see only about a
    $15/year savings in the months we are *NOT* heating the room the water
    heater is in. If we are heating the room anyway, then we lose nothing by
    adding some heat from the water heater. Counting only half of the year,
    we get about an $8/year savings for the tankless compared to an equally
    efficient (burning) tank system. Most of the tankless systems are not high
    efficiency systems. By the way, this is comparing two systems that are in
    standby 100% of the time. If you actually use hot water in hour house,
    the $8/year number will be smaller.

    Dave

  11. #191
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking Sounds Great

    As our great and all knowing president George Bush once stated

    it all sounds like "fuzzy math " to me.....


    that is why I have just installed a simple gas meter
    directly to my 75 gallon Bradford White heater.....


    no more "fuzzy math" for me....
    I am just going by the numbers for the month or year....


    but now I am very reluctant to install that tankless heater,
    now that I have a flooded out downstairs home and have
    other projects more pressing on my mind....

    Its all beginning to become a blur of " fuzzy work." this summer.

  12. #192

    Default Tankless costs

    I'm a plumber in Park City,Utah.I live at 6500 ft.I have a lot of customers sold on the "green" tankless units.I refuse to install them.The water comes into the houses at around 40 degrees,and we have very hard water.Plus,we're in a high desert.I haven't seen any coments on how much water is wasted with a tankless WH.Why not put a recirc pump on the water heater tank?Instant hot water.Insulate the hot water pipes in the house that you can get to.Drain the sediment from the WH tank every once in a while.And change the annode rod.The tank will last longer and you'll have a lot of hot water.I installed one Rinaai tankless,and the factory rep said to come out and check it(customer's request),he charges $60 an hour,plus travelling time both ways.They needed a new electric panel to have enough power for the tankless.And they're very unhappy with the unit.Too expensive.But the tankless people seem to have a great PR machine.All of the "green" customers I have want one.I tell them to call another plumber.

  13. #193
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking people are flocking to green

    Quote Originally Posted by ted01 View Post
    I'm a plumber in Park City,Utah.I live at 6500 ft.I have a lot of customers sold on the "green" tankless units.I refuse to install them installed one Rinaai tankless,and the factory rep said to come out and check it(customer's request),he charges $60 an hour,plus travelling time both ways.They needed a new electric panel to have enough power for the tankless.And they're very unhappy with the unit.Too expensive.But the tankless people seem to have a great PR machine.All of the "green" customers I have want one.I tell them to call another plumber.
    You are probably doing the right thing,,.refueseing to install them.

    their are a few companies in our town that install them for about 3500.
    and they dont care how they perform....



    tankless people have a great PR machine.... .

  14. #194
    Master Plumber nhmaster's Avatar
    Join Date
    Jul 2008
    Location
    S. Maine
    Posts
    2,039

    Default

    I believe the average pay back period for tankless water heaters is somewhere around 15 years. I also believe that the majority of them will have to be replaced it the end of that time. like most "green" technology the hype is far more important than any actual savings. Here's the big factor though. Those folks that could really benefit from technology that would ACTUALLY save them some money can rarely afford the price of the equipment or the installation. Some scrape and borrow to purchase these products only to find that they have in reality saved nothing at all and in fact are now paying more if finance charges are added into the equation. These things are nothing new. Paloma and ELM have been on the market for years. We hated them then because they were service nightmares and did not live up to expectations. Why are we so in love with them now? Same crap, different day.

  15. #195
    Master Plumber master plumber mark's Avatar
    Join Date
    Feb 2005
    Location
    indianapolis indiana - land of the free, home of the brave....
    Posts
    4,243
    Blog Entries
    1

    Talking damm, a year has passed......

    I started the experiment on Sept 16th 07.....

    the gas meter was on 0000000


    now the date is Sept 28th....08.......

    Looks like I have been sleeping at the wheel


    anyway the meter is now at 41521.00

    so basically my 75 gallon gas heater used

    41,521 cu feet for one whole year.....

    I went over the mark by 12 days.. ...too bad..
    ..




    now all that is necessary is to figure out how much
    I pay for a cubic foot of gas..in Indiana...


    and I can tell you about what it cost me for the year..

    and then divide by 12 and tell you howmuch it cost per month...


    time flies when you are having fun.....


    now I got to bring myself to installing a Takagi in my home and
    let it run on the meter for a year...............

    ....

Similar Threads

  1. Tankless info from consumer reports, Tankless...Bahhhhh
    By nhmaster in forum Tankless Water Heater Forum
    Replies: 117
    Last Post: 11-28-2011, 12:26 PM
  2. Replies: 10
    Last Post: 04-26-2010, 08:09 AM
  3. Tankless?
    By mvmone in forum Tankless Water Heater Forum
    Replies: 4
    Last Post: 08-17-2009, 11:36 AM
  4. Tankless.
    By canton in forum Plumbing Forum, Professional & DIY Advice, Tips & Tricks
    Replies: 4
    Last Post: 03-26-2007, 05:30 PM
  5. Kohler vs. Toto - An interesting experiment
    By jk60 in forum Toilet Forum discussions
    Replies: 6
    Last Post: 01-08-2006, 01:42 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •