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Piping Diagram Comments

Post in 'The Boiler Room - Wood Boilers and Furnaces' started by blackdoglabrador, Feb 28, 2013.

  1. blackdoglabrador

    blackdoglabrador Member

    Joined:
    Feb 19, 2011
    Messages:
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    Loc:
    Mt Holly, VT
    I am in the process of building Tarm Innova 30 System from scratch and would like some input. I have made the attached piping diagram and I have two major questions:

    1. Will the tees I have that tie the storage into the supply and return piping allow for proper flow of storage water to radiant circuits when there is a demand (and not short circuit through the boiler that has a termovar loading unit on it) (tee are called out in red on boiler piping 1.pdf )​

    2. Looking to reduce number of pumps and be energy efficient. Can I use one Grundfos Alpha like shown with zone valves to control each zone (including DHW)? My design is based off the second sketch from Tarm (Tarm with Zone Valves.pdf) which is similar to all of their sketches show a wood boiler circulator plus a circulator at the zone distribution. I would like to limit that. ​

    Any help or input is appreciated. I am hoping to start piping this weekend. As all the major pieces are in place and I have a brand new turbo torch I am itching to fire up.

    Thanks again!


    Please note my drawing does not show the following because of clarity
    1. Wiring
    2. Feed water piping
    3. Thermometer which i will add throughout
    4. Drain points which I will add throughout
    5. Detailed zone hook up (zone valves, mixing valves, etc.)
    6. Dump Zone

    Attached Files:

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  2. arngnick

    arngnick Member

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    Feb 15, 2013
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    Loc:
    Mansfield, PA
    Good looking diagrams! I am by no means an expert but I will give it my best opinion. I think the Tees will do fine if your heating zones have a large demand in all zones and you are burning a fire you may not be putting much toward storage at that time. You could oversize the tees if you are concerned but I do not think it would be nessasary. As far as the Alpha pump it will depend on the length of the the radient zones and the size of pipe that is used. I am a little confused on the placement of the zone valve on the storage not sure what BLT is but without knowing how it is conrolled I can see it blocking the storage from your zones.
  3. blackdoglabrador

    blackdoglabrador Member

    Joined:
    Feb 19, 2011
    Messages:
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    Loc:
    Mt Holly, VT
    Thanks for the input.

    The blt is a controller that is sold by tarm. It is the controller that determines whether fossil fuel boiler fires or the zone valves open and allows water to flow from storage base on info from a atorage tank aqua stat.
  4. arngnick

    arngnick Member

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    Loc:
    Mansfield, PA
    So would the zone valve be open most of the time with the exception of when the fossil fuel boiler is on?
  5. blackdoglabrador

    blackdoglabrador Member

    Joined:
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    Loc:
    Mt Holly, VT
    Zone valve would only be open when storage tank aqua stat read it was above its set temp of say 140 degrees
  6. arngnick

    arngnick Member

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    I now understand the use of the zone valve makes sense. I think the setup makes sense let see if anyone else will weigh in...
  7. ewdudley

    ewdudley Minister of Fire

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    The heating zones are labeled as 'radiant'. Do you mean radiant as in floor radiant or panel radiator, or do you mean baseboard or some such?

    If low temperature radiant then need some mixing scheme for radiant loads and Thermovar diverter can go away, but would need a small separate pump for DHW and a small diverter like a Taco 5000.

    In any event in answer to your second question, Grundfos Alpha or Wilo Stratos with multiple zone valves is the way to go for pump efficiency when feeding multiple independent zones.

    Seems to be a bit more piping and valves in the middle than optimal. Load side could connect to the far end of the top storage tank manifold and reverse return to the other end of the bottom manifold, and vice versa for the boiler to storage tank manifold connections.

    Any tank volume below the lower storage tank ports will be lost for storage purposes.

    With 1.25 inch or larger piping from boiler to storage tank manifolds, many have found the Thermovar loading unit will provide automatic power fail heat dump protection, YMMV.
  8. blackdoglabrador

    blackdoglabrador Member

    Joined:
    Feb 19, 2011
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    Loc:
    Mt Holly, VT
    Would it still be any benefit to keep the thermovar (160 degree set point) just for the dhw, assuming i use mixing valves on the radiant loops? I am trying to keep the temps low on heating devices so I can maximize storage. I might later add a unit heater via flat plate heat exchanger in the garage that might be a higher temp heating device, but is the efficency gained by that thermovar worth the putting it in (for circuit I might only use on weekends)? I do already own the valve, but if I am thinking of it right this valve may never operate because my return temps will always be below 160. Assume the dhw will have a delta temp of probably 30 degrees (is that an accurate assumption?), and my highest operating temp is going to be around 190.
  9. ewdudley

    ewdudley Minister of Fire

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    There would be benefit, but for loads up to about 70000 btu per hour you can use a smaller, less costly ($100 or so), adjustable diverter like a Taco 5000. Then you could tune the DHW return temperature to be as low as possible while still providing hot enough DHW at a sufficient flow rate. (I mention the Taco 5000 as an example of the type of valve I'm talking about. Any valve of that type that is adjustable in the range of temperatures that would make sense for what you're doing would work.)

    Seems like the garage circuit and DWH circuit could be fed off the same high temperature circuit with zone valves and a diverter. But like you say, at 160 degF the setpoint of the Termovar may be too high for your purposes. You can get lower temperature guts for the Termovar, or sell the Termovar and get a smaller adjustable valve.
  10. I've been using the tarm pt1 diagram. It's not the cheapest way to plumb in storage but it works great. It couldn't be easier for the end user. Load the boiler hit start and walk away and let the system do its thing.

    In place of the termovar labeled tv2 I'm using a danfoss with the 140* element. I have a 160 element to put in but don't see the need. I'm using baseboard heaters and my house will stay warm with the low water temps in the primary loop. I don't reload my boiler until storage is down to at least 120. Works for me...

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