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    smart 50 with tankless water heater (15 Posts)

  • britch1 britch1 @ 11:27 PM
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    smart 50 with tankless water heater

    Would I be able to keep a idwh at a constant temperature using dhw and a pump to
    shower etc.and then use the side loop to heat a 1000sqft house separately 4 loops 1/2" × 250' each to heat. Cant afford boiler right know . Using aquastat and taco zvc 6 with priority. My ghetto setup is takagi and alpha on high to manifold and it rips at 140*out 120* in and 70+* on floor , where can I find a piping layout on this, pump size to force water into dhw and out of the big part of tank where the domestic hot outs , im thinking inner coil with the alpha and a bigger pump to keep tank hot when needed, seeking comfort.
  • Snowmelt Snowmelt @ 12:35 AM
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    What the heck

    I have no idea of ehat you said, but I think you have it back words you can you the takagi and a flat plat hex with a stainless steel 009 pump and a potable water expansion tank, also you would need a flow meter to turn the heating off when using domestic water.
    Why do you have a 6 zone control board?
  • heatpro02920 heatpro02920 @ 7:10 AM
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    What is your heat loss

    Do you have pics of the system?

    The price of a smart 50 can buy you a small heater, better idea than what I think you are thinking..

    That tankless water heater is not going to like the close delta for long, I hope its not propane, you will get soot and poor efficiency with a 20 degree delta for long periods of time... When using a tankless for heat zones, I would use a 3 way zone valve with an aquastat that recircs the water without sending it back through the HX until the delta opens up, I have seen people do it with mixing valves too.

    And are you saying you send 140 degrees to your floor?
    This post was edited by an admin on March 15, 2014 7:15 AM.
  • britch1 britch1 @ 11:07 AM
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    high heat loss

    At this point im about to r-19 insulate under house , r-13 walls , blow in thick attic , say smallish house divided in 4 with equivalent of one 6' x 7' dual pane window in each got smart tank real cheap , im on a water well as well, is my idea worth pursuing? Thanks
    This post was edited by an admin on March 15, 2014 11:09 AM.
  • Zman Zman @ 11:41 AM
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    First off, The outer jacket of the smart is steel. It needs to be in the closed heating loop.
    Is the alpha you have stainless? It needs to be if you are using it on the domestic side.
    The alpha is idea for zoned radiant loops, it is kind of a waste to use it on the domestic side where you just need a fixed speed.
    I think what you are proposing will "work"  I don't diagree with you that it is "ghetto".
    I have not done on of these. Folks that have seem to have trouble with the tankless controls and the delta t.
    If you post a drawing you will get more feedback.
  • britch1 britch1 @ 10:18 PM
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    stainless steel alpha

    Thanks people i will give the ss 009 a crack. Just got it all put together a few months late ,its like 75 outside . Next fall im sure to be asking questions, this website is the sh*t! Plus I like the math problems!
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  • britch1 britch1 @ 10:56 PM
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    chicken scratch

    So what im getting at is the alpha pumps into 8 gallon internal tank then floor loops . If I keep the big tank hot using aquastat knob on top of tank , taco controlled pump ( new 009 or whatever) goes to tk jr. A mixing valve to shower etc. I would have the ability to lower temp at summer time a Carpenter that sits in traffic alot thinking .thats why.thanks for any input anybody
  • Zman Zman @ 12:59 AM
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    I though I recognized the dialect.
    The plan looks pretty sound. The alpha needs to "pump away" from the expansion tank. I think I would just move the pump.
    Where does the 009 go?
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    009 stainless for the takagi

    Unfortunately we have a young guy that inherited daddy's biz name and uses Rinnai and aqua stars to do in slab heat all the time. It's too bad cause his work is good enough to eat off of, it's the type A personality and own computer designing that falls short. Cheapest boiler //// errr tankless install option ever..
    The takagi calls for a 009 stainless circ, (24.6ft/[email protected]) they no longer make a bronze version, thus the $400 -009SSF4 cost. Used for heating on city water, expect a short life before heat exchanger pin holes.
  • heatpro02920 heatpro02920 @ 1:14 PM
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    I think there are better options...

    I honestly think you are going to end up chasing your tail on this one, the money spent on all these parts can get you where you want to be the "rite" way... We aren't supposed to talk money but if we had an idea of your budget, I think there are better options to achieve your goals..
  • britch1 britch1 @ 10:01 PM
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    15,000-20,000 btu.

    Heat loss when im done or very small heat use. Combi boiler maybe but quite pricey , any options I am open to , im here to get advise and learn a little. Hit me with high budget and low budget options , im all about it . All I need is a basic layout and I will conform. Thanks people!
  • SWEI SWEI @ 12:39 AM
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  • britch1 britch1 @ 11:29 PM
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    no electric water heater is going here

    I do like the idea of putting a heat exchanger in my fire place useing the rumford designed fire box and piping that to the tank as well .What is the downfall of this design posted ?any input?
  • RobG RobG @ 4:29 PM
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    The Downfall

    The down fall of that design is that by the time you buy and install all the components (and at a glance, it needs another pump after the mixing valve and another expansion tank on the open loop) you could have bought a combi boiler and have a system that WILL work. As Heatpro said, you are chasing your tail trying to build a cheaper mouse trap. Price out all the materials, factor in your time (don't forget all the time to make it work ).
    This post was edited by an admin on March 29, 2014 4:58 PM.
  • britch1 britch1 @ 11:48 PM
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    still think its a good idea

    I know what I need and will try it anyways .
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