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Wood boiler , pump at boiler , ON/OFF

Hello all, Ok I have a wood boiler in my detached garage , works great had it for years , I hooked it all up myself by learning from sites like this ,, my issue is: I have a Taco 0011 at the wood boiler that pumps from garage into the heat exchanger hooked into my old oil boiler , in November when I fire up my boiler, it does not go out until May 1st, the pump runs 24/7 for that entire time, it ends up costing me a pretty penny , I want to wire up the wood boiler pump to activate when the main house zone calls for heat, I will never have pex tube freezing issues as I know (from experience :) ,,because it take at least 15 hours for the cold/frost to hit my buried pex. How do I wire the pump at the boiler and what do I wire it to ? I will bury the wires now. Do I need to add any other controls? Any help is appreciated, I hope I explained my need ok. thank you in advance.

Comments

  • hot_rod
    hot_rod Member Posts: 22,020
    Any wires running between them
    If you had some low voltage wire to put a sensor out at the wood boiler here is how I run mine
    A differential control senses both boilers. Any time the wood boiler is hotter than the house boiler it starts the pump, or circulator😉
    when the house boiler is within say 5 degrees it shuts off. 
    So basically anytime the wood boiler has heat to off the 0011 runs

    .

    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Zman
    Zman Member Posts: 7,561
    I assume the 0011 is attached to the boiler powered and is at that location?

    If so, I would think setting a relay at the 0011 and running control wires back to the house would work nicely. You could use 18-4 (or more) direct burial wire intended for irrigation controls.

    Something simple like a Taco SR501 would work nicely for the 0011. I would need to know what existing controls you have at the boiler to determine how the "switch" end would work.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • nehcorp
    nehcorp Member Posts: 3
    Hello Zman, yes the taco is hooked up at the boiler with a simple power plug, it runs independent of all other controls. I will bury some 18-4 and try the SR501 or similar. Hot-Rod I have a fairly nice "positive shut off" at the blower so it seals up nice. I should never have unneeded heat to off. The wood boiler dampens down to a smolder when not needed. My only issue with the entire system is this unneeded waste of electricity keeping the power hungry pump running for 5 months straight. Thank you both very much for the input.
  • Ironman
    Ironman Member Posts: 7,366
    Do you heat your domestic from the wood boiler? If so, and if you have a side arm or a plate heat exchange at the water heater, then you'll need to leave the pump on constant circulation to heat your domestic.

    The pump probably doesn't cost as much to run as you might think. At 12 cents per kWh, it would be about $10 a month.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • hot_rod
    hot_rod Member Posts: 22,020
    How well is the piping from the boiler insulated?  That can be a substantial loss, especially if it gets wet. That would more of a concern then the small power consumption, as @Ironman mentioned.
    A simple set point control that keeps the boiler off until it reaches 140f would work with what you have now, no additional wiring.

    The differential control gives you two temperature points and maximizes the OWF contribution.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • nehcorp
    nehcorp Member Posts: 3
    Bob, I have the best insulated pex (Thermopex), no leaks nor do I have much heat loss , less than 1.5 degrees from wood boiler to oil boiler, I can live with that.
    Iron man, I heat my domestic , with a house full of females I have to, the domestic hot water has it's own zone that calls for heat when needed. In fact everything works great, no issues, I just do not like the pump running for 5 1/2 months straight. thanks
  • Ironman
    Ironman Member Posts: 7,366
    I know exactly what you mean: I have six daughters, plus my wife likes to soak in the tub every night. They're the reason that I put the ODWB in.
    They're all grown and out the house now, except one.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • GroundUp
    GroundUp Member Posts: 1,889
    Be prepared to replace that 011 if you intend to cycle it, and then plan on replacing the wood boiler from thermal shocking it with cold water several times a day and overheating it several more due to lack of water jacket mixing. If anything, you'll want to set it up with a primary (boiler) loop pumping 24/7 to keep the water jacket mixed and then another circ pumping the loads on demand. But then you're back to square one spending $10 a month instead of only $7. It's a great idea in theory, but a poor idea in reality if saving money is the objective