Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

System pump help

Fid2973
Fid2973 Member Posts: 6
Question 
1. is it better to use 1 pump for loops going to 2 different levels in a house ( between joists rad. Heat 6 loops max per floor) or pump / loops on each floor . If I do the first it will save me from using two pumps ( thinking it would save on electricity. Don’t care about buying the extra pumps .) 

my system is this outdoor wood boiler for now. Going to a indirect heater or tank. Then coming off tank for system loops. 
I was looking at the Caleffi manifolds with alpha pump. Wasn’t sure if building my own would be worth it. But if I use only 1 pump for all I will need to build because of head height. 

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 18,941
    You are forgetting that the head pumped against in an hydronic heating system is independent of the building height -- it makes no matter whether it is one story or six. You do need more head to purge on higher floors -- but not to circulate. So one pump is fine.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Fid2973
    Fid2973 Member Posts: 6
    Thank you how about power consumption 1 big pump vs 3 small pumps.
  • Ironman
    Ironman Member Posts: 6,868
    It's a lite more complex than you may realize. Pumps are selected based upon gpm and resistance to flow (dynamic head). Those numbers come from the system's characteristics: required btus, pipe sizes and lengths, components, piping methods, etc.

    Without those details, it cannot be determined whether you should have one or three circulators. The control strategy also factors in that. But economics is the least factor. The laws of physics will outweigh the laws of economics every time.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • Fid2973
    Fid2973 Member Posts: 6
    Thanks I appreciate that
  • hot_rod
    hot_rod Member Posts: 16,307
    If you running that wood boiler, things change a bit. Mainly you need to overcome any pressure drop in the piping from boiler to loads.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Fid2973
    Fid2973 Member Posts: 6
    Thank you. Yes I was wondering if temps would really change the main system. It’s going to have  a 10 deg. Swing on boiler. I was wondering if a electric thermostatic mixing valve would help hold temp better on the indirect heater. ( outdoor reset )
  • hot_rod
    hot_rod Member Posts: 16,307
    Got a sketch of how it is piped. Is the indirect being used as a heat exchanger between the wood boiler and the distribution? I assume the wood unit is an open unpressurized type?
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Fid2973
    Fid2973 Member Posts: 6
    yes, and yes that was the plan it is still in the drawing stage ( I’m still learning a lot) . I really just want to keep it simple. I right now just turn the boiler down on warm days or house gets hot now . Registers in forced air system. So you know I’m building a house on to a (1864 homestead)house. 
  • hot_rod
    hot_rod Member Posts: 16,307
    OWF bring along a lot of baggage :) Correct size piping is important. Quality, large diameter underground insulated piping is worth the $. Piping can make or break it. A simple control wiring to maximize all components is hard to keep "simple" Unless you manually operate valves, pumps, switches, pretty much tending to it hourly.

    But after all that you get around 40% efficiencies with perfect wood, burned hot, not turned down, and never left to idle and smolder under oxygen starved conditions. Unless making charcoal is part of the plan?

    But seriously, start with an essay of how you want it to operate. Numerous examples of essays in Idronics 10.
    Next a piping drawing that allows that operation.
    Then a wiring diagram, also see the ladder drawing examples in Idronics.

    My system had a wood gasification boiler, 500 gallon buffer, 160 sq feet of drainback solar thermal, mod con back up, and a DHW flat plate. I controlled it all from a single Resol BX control. With about 12 sensors.
    https://www.resol.de/en/produktdetail/68
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Fid2973
    Fid2973 Member Posts: 6
    I do have a good underground pipe 1” burner is 50’ from house. Also thought about a buffer tank. The one I have on hand but never installed was a 500 gallon lp tank. Just didn’t think it was worth it. My stove hold 450 gallons now. The weather we are having now 40 , 55 degrees. I load only once in 24 hrs . 5 pieces as big as a 2 liter soda. If it gets over 60 days and 40 at night may load every other day. I’m 60 miles north of St. Louis but in Illinois. House has zero insulation. ( seriously ) I did really think about putting controls for each room. Floors would be main source and maybe a radiator if I couldn’t make enough btu’ thru the floor. But I think I will have more than enough. 16” joists spacing 8 inch spacing on 1/2” thermal fin c plates. Thermal fin said I would be well into 30 btu per square foot. I would love to solar but it would be all electric. Having a farm I have all the room in the world to put stuff. Lol. I’ve only cut 6 trees down in 12 years most people just give me the wood. Thank you I do need to read a little more about systems. I do understand gal per minute you can push through the size of the line and pressure drop in the line. It’s just putting it all together and what control systems are out there I don’t know. That you again I like reading your post on other peoples problems.