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Is my hydronic system flow direction correct?

jrh00800 Member Posts: 4
After some quick searches on proper hydronic system layout it would appear that my circulator is installed backwards (I verified the flow direction cast into the circulator for the arrows in the picture). I would also tend to think that you would want the higher fitting on the boiler to be the outlet not the inlet. This may explain why we hear noise in our system during the winter months? Thanks for any feedback.


  • JStar
    JStar Member Posts: 2,752

    You are correct. They did put the circulator on the supply (good) but it is indeed upside down (bad). You can make a quick fix by flipping it the right way.

    What noises do you hear?
  • jrh00800
    jrh00800 Member Posts: 4
    Can hear "rough" flow through pipes

    I started hearing flow through the pipes towards the end of the winter season, it isn't bad but not normal either. I was going to get an air separator and started looking at the current setup and started scratching my head....thanks for the reply, I will flip the circulator.

    The system does not have any air separation devices / air traps that i know of. Good idea to install one of these as well? Was looking at a spirovent vertical mount, I may need to move the circulator up in order to fit it in there.
  • Rich_49
    Rich_49 Member Posts: 2,563

    install that air eliminator . The Spirovent is a good unit . Move the circ to the other side of that as you stated .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • SWEI
    SWEI Member Posts: 7,356
    Expansion Tank

    Is that an old-school non-bladder expansion tank?
  • jrh00800
    jrh00800 Member Posts: 4
    I believe so

    I would like to get a new bladder style expansion tank, and would like to use the same fitting location. I suppose I will just have to hang the tank higher above the unit in the proper orientation with an air vent and a line running down to the existing connection right?

    I don't think the expansion tank is really doing anything as there is no backflow prevention on this unit. I think the water is just expanding back into the water supply line. I need to fix this as well. Same thing with my water heater. And the fun just keeps piling up.
  • Zman
    Zman Member Posts: 6,530
    edited August 2013
    In more ways than one...

    It looks like your boiler is piped backwards, the supply and return are usually the other way on a boiler of that type. You are also pumping into your expansion tank. This will account for all the air you are hearing. The air eliminator is a good idea. It will not work with the old school expansion tank. It looks like you have directional zone valves. Which way are they oriented? Are there other check valves in the system? Yes, you absolutely need a backflow/prv combo.

    By the time you correct all this, you might ask yourself, "do I just replace the boiler?"

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • jrh00800
    jrh00800 Member Posts: 4
    Thanks for pointing that out

    One of the zone valves does have a flow direction on it and it points in the opposite direction of current flow. Might explain why this zone hasn't worked in quite a while. However it is the basement zone which we never use anyways. The other two zone valves don't appear to have a direction but if they did I would imagine they would match the marked zone valve. The two zone valves that don't have a direction that I can see are WR 1361-102. Should these be directional? They seem to work fine.
  • Zman
    Zman Member Posts: 6,530
    No arrow

    Usually they will have an arrow if they are directional.

    When you put them in backwards they usually just "hammer" loudly/

    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
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