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Triple Tube Smart40 Indirect Hot Water Heater

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Comments

  • DH123
    DH123 Member Posts: 58

    This is what it’s supposed to be according to the information I could find.
  • neilc
    neilc Member Posts: 2,689
    that white tube isn't kinked at all, is it?
    looks ok in the picture, but what about where it meets the dial control?
    assuming this checks out,

    are you sure the dip tube is sealed in the cold inlet, and not short circuiting / bypassing across the top of the tank?
    known to beat dead horses
  • hot_rod
    hot_rod Member Posts: 22,022
    Maybe this link will help you see how a capillary tube control works

    The long grey part is a very small diameter copper tube filled with a liquid.  As the bulb at the end changes temperature the fluid pushes a bellows to activate a set of contacts 

    If that tube gets damaged, kinked or broken so fluid leaks out, the control is shot

    Has the tube been damaged in any of them!
    It is not a wire!

    If you have an old one, open it up so you are clear on how it works 

    https://www.industrialcontrolsonline.com/training/online/%E2%80%9Ccap%E2%80%9D-tubes-temperature-sensing-elements
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • neilc
    neilc Member Posts: 2,689
    I got 1 more try,

    the wire back to the taco,
    at the tank,
    it's connected to the 2 outer terminals?
    C and 1 ??


    known to beat dead horses
  • DH123
    DH123 Member Posts: 58
    Hi Neil
    Yes it’s the outside contacts the inside is ground.
    I think when the red zone 6 light came on we proved everything was wired correctly it’s a matter of the aqua-stat to want to call for heat.
    Jim
  • Jamie Hall
    Jamie Hall Member Posts: 23,167
    I notice -- finally -- that you have the temperature control almost all the way set to cold? And is the capillary bulb actually seated in the well? It has to be touching the sides of the well...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • hot_rod
    hot_rod Member Posts: 22,022
    Does the relay box have a switch for domestic hot water priority? Maybe it got switched off?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Zman
  • DH123
    DH123 Member Posts: 58
    Hi Bob
    That was good reading about the capillary control. I just thought that bulb changed resistance based on temperature. I guess it does but there is more to it than I thought.
    I was looking for a priority and didn’t find one.
  • DH123
    DH123 Member Posts: 58
    Hi Jamie,
    I bottom it out about 30” to the bottom. It feels pretty snug but I really don’t have any control where it’s sitting 30” in the dry well.
  • neilc
    neilc Member Posts: 2,689
    drop an 1/2 oz of cooking oil down the sensor tube (?)
    as a transfer agent
    known to beat dead horses
  • neilc
    neilc Member Posts: 2,689
    I'm back to this,
    neilc said:


    are you sure the dip tube is sealed in the cold inlet, and not short circuiting / bypassing across the top of the tank?

    known to beat dead horses
  • DH123
    DH123 Member Posts: 58
    Hi Neil,
    Yes I am positive, I took a shower removing the cold line Friday. Took the picture of the tube
    and reinstalled the tube.
  • pedmec
    pedmec Member Posts: 959
    That's a very thin copper capillary tube that is connected to the bulb at the end. it has a fluid in it that as it gets warm it expands and causes the switch to change position. You need to be extremely careful playing with the capillary tubing as any kink in the tube will render that thermostat useless. A kink can close off the liquid to the switch mechanism. Which considering how many have failed could be whats happening. the last thing I do is blame a defective device on the manufacturer. I find that its mostly the installer who doesn't understanding the device and how its function. This is not a shot at you. It also applies to techs in the field. Although manufacturers do send out defective parts its really the last thing i would look for.
  • Jamie Hall
    Jamie Hall Member Posts: 23,167
    DH123 said:

    Hi Bob
    That was good reading about the capillary control. I just thought that bulb changed resistance based on temperature. I guess it does but there is more to it than I thought.
    I was looking for a priority and didn’t find one.

    It doesn't change resistance Get over it! It's a switch. It's either off or on!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    SuperTech
  • hot_rod
    hot_rod Member Posts: 22,022
    If jumping the control out, the system works, It can only be the aquastat

    My money says the cap tube is getting kinked, especially with all the fussing it has seen!

    Do you know how to use the Continuity setting on the meter?

    remove the word resistance 🥴 going forward, I’m worried about Jamie’s blood pressure.

    Disconnect the wires from the control, pull the cap tube out if the tank. Warm and cool the bulb, what does the meter tell you when In continuity position?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    Larry WeingartenZmanSuperTech
  • DH123
    DH123 Member Posts: 58
    That is the direction I was going when I could short the contracts toward the Taco and it worked. I was acting like the switch, so I did what you are indicating. As the bulb cools the aqua-stat switch closes asking for heat. I posted 2 pictures showing this. I’m in complete agreement however I have 3 aqua-stat acting in the same fashion. This is why I indicated maybe I should get a long temperature gauge to find out what the internal temperature of the dry well is but I don’t have a cross reference to the aqua-stat open and close temperature. Sorry about the reference to resistance I’ve been an Electrical Engineer for 35 years; continuity, resistance, open, close, high low impedance are all used and understood interchangeably.

    I’ve got a rep from TriangleTube stopping by Wednesday what questions should I ask him?
  • DH123
    DH123 Member Posts: 58
    Hi Pedmec
    Good post on the aqua-stat. This could be user error it’s very possible that
    I’ve put a small bend in the device affecting the flow of the internal liquid.
    Jim
  • JimP
    JimP Member Posts: 87
    Where was your old heater leaking from? Could you post a photo of your the leak?
  • HVACNUT
    HVACNUT Member Posts: 5,804
    Where the wires connect to the temperature controller, I believe there are THREE terminals you can connect to. Common, opens on temperature rise, and closes on temperature rise. Check to make sure the wires are on the correct terminals.
    And beautiful soldering job BTW.
  • DH123
    DH123 Member Posts: 58
    Thank you for the soldering comment getting to be a lost skill.
    The package said to connect the thermostat wires to the outside terminal post.
    C &1.
    The original Smart40 was a great H20 heater 18 years and not one issue.
    I’m paying for that now.
    You can can see water on the floor exactly where it was coming from I don’t know.



  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,718
    I am so glad that I did not get involved with this discussion. I would have given up on the whole resistance vs. dry (NC) contact that break on temperature rise thing about 20 comments ago.

    This is where someone with experience with this type system might need to show up and get paid to solve this problem. Some folks have more patience than I do.

    Good luck with your cold shower problem @DH123.

    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
  • Zman
    Zman Member Posts: 7,561
    If you jump the wires at the smart and let it run for a while, does it drop out like it is when connected to the aquastat? You may have a weird one where a bad spot in the wire or a failing relay or transformer is opening the circuit once it heats up. Also, what is the voltage when it closes?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • DH123
    DH123 Member Posts: 58
    Hi Zman,
    No it will run until the pressure relief valve lets go.

    Actually a factory rep, and a technical guy and a salesman stopped by to check it out yesterday. They gave the job a thumbs up and said they have been to many so called professional plumbers that didn’t do as nice a job. That mad me feel pretty good.
    However when they could short the terminals back to the control they said it is absolutely the aqua stat.
    They wanted to know if I had measured the internal resistance of the device when it was working and when it wasn’t. Measure the internal resistance of the device you mean thevenin resistance but it’s a switch. It’s a switch. it’s either 0 or infinity.

    Interesting the bulb tube is actually filled with kerosene and operates on pressure as some have indicated the line should be free of kinks.

    Fortunately we have $100 piece of junk electric hot water heater I picked up before I re-plumbed the circulators that is working fine ( thank god). This Smart40 replacement was covered because the original Smart40 had a lifetime warranty on the tank and it started to leak. Because of the problems with this Hot H20 heater my wife has lost faith in this product and wants to move on.

    What do people think about a heatpump Hot H20 heater? They offer a good rebate from the state and I hear positive things about them. I’m also really concerned what is going to happen to the cost of #2 oil.
  • Jamie Hall
    Jamie Hall Member Posts: 23,167
    The thing about the heat pump is recovery. If you get a big enough one --at least twice the capacity of your indirect -- you may not have a problem. Otherwise it will switch to resistance heat, and when it does it is no cheaper to run than any other electric water heater.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • DH123
    DH123 Member Posts: 58
    That makes sense. Thanks Jamie.
  • Zman
    Zman Member Posts: 7,561
    The thing to consider with the heat pump is that by design it pulls heat from the space and puts it in the water.
    Your smart tank is still viable. It is either the dip tub or the aquastat (assuming the voltage from the taco checks out). With a good aquastat you can hear (and verify with a meter) the temp that it clicks in. It’s one or the other…
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • neilc
    neilc Member Posts: 2,689
    how did we get to heat pumps ???? #smiling

    didn't the reps replace the aquastat at the smart ?
    known to beat dead horses
  • DH123
    DH123 Member Posts: 58
    The Smart40 is fixed.
    After (4) aqua stat replacements and the rep saying it’s the aqua stat
    the supplier agreed to provide me with another Smart40. When I started to remove the domestic water hook up I realized what was wrong.
    This Smart40 had (2) dip tubes one on the cold and one on the hot.
    When we wanted hot water it was pulling from the cold dip tube at the bottom.
    After removing the second dip tube Plenty of HOT water😀. That occurred Sunday afternoon.

    Saturday morning I was going over 9 years of #2 oil receipts and it became apparent to me
    I can’t afford to keep running my boiler all summer to make hot water. I live in VT and we go through about 900 gallons a year. 125-150 are between June1 and October 1. Heat pump
    information indicates that you can produce a years worth of hot water for $150-&200.
    I’m going to research further over the winter but at $5+ a gallon for oil it just doesn’t make sense.

    Thank you to everyone. Sorry I rustled a few feathers with my slang.

    Jim Urquhart
    Whit River Junction, VT


  • hot_rod
    hot_rod Member Posts: 22,022
    there are a number of folks on this list running HPWH, with some time on them now for some actual feedback.
    I played around with one in my shop, here are some observations. An 80 gallon AO Smith brand.
    Mine has 4 operating options. In efficiency, it is HP only. I suspect most all brands have that option to run HP only.

    Recovery is slow from a cold 55° fill to 120F took around 10 hours in HP mode. If you want faster warm up or expect guests hybrid or electric mode could be enabled.
    Electric mode disables after 48 hours, a nice feature

    It is a bit noisy, for 12 hours!, be aware of that when you locate it.
    It was discharging around 46° air when running.
    It would not be suitable for a closet of small room application.
    The heat for it to "pump" needs to come from somewhere Located near a boiler would be good in heating months.
    You need a drain nearby for condensate, or a pump to get rid of the condensate.

    It may be a perfect fit for you home.

    Here is the manual to read about installation
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • pedmec
    pedmec Member Posts: 959
    Why was there two dip tubes in the tank? How did that happen?
  • DH123
    DH123 Member Posts: 58
    Pedmec- that is a very good question.
  • neilc
    neilc Member Posts: 2,689
    thee ole double dipped smart 40,
    who da thunk ?
    known to beat dead horses
  • pedmec
    pedmec Member Posts: 959
    Looking at the manual it looks like its not piped correctly. The other long tube is for the drain connection to get water out of the tank in a tank in take design. The tank requires a tube that reaches to bottom of the tank so a pump can be used to drain the tank. Without that drain connection you have over 400lbs of water sitting in it and good luck trying to move it if you have too. Wont matter until it fails. The long tube should have been in the drain connection. The pressure relief valve should be on the hot water outlet with a tee instead of a 90 and the drawoff in place of the pressure relief valve.
  • DH123
    DH123 Member Posts: 58
    All I can tell you is it works a lot better with one dipper than with 2.