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Help! How do I fill my in floor heating closed system?

bbauer Member Posts: 2
How would you fill this type of in floor heating system set up?


    EBEBRATT-Ed Member Posts: 13,450
    I don't see any city water make up there so i suspect this is a glycol system

    Does this system have antifreeze in it?

    If it is antifreeze you going to need a pump.

    If it just is water you can fill it by feeding water into the drain valve that you have the buckett under it. Use a regular garden hose and a female x female hose adapter (or a washing machine hose) bring it up to 12 psi. Yo will have to bleed the system
  • bbauer
    bbauer Member Posts: 2
    Yes it is a glycol system in my shop. So I just need a pump and say a 5 gallon pale with the glycol/water mix, hook that up to the drain valve and pump it into the system? Do I bleed it from the pressure relief valve attached to the side of the boiler at the same time? If this is all correct that is.
    EBEBRATT-Ed Member Posts: 13,450
    Do you know how much the system holds?

    Either way buy a jug of glycol and you want a 50/50 mix of water and glycol you can buy premixed or mix your own but you have to pump a mix in so you know it's right.

    Hook up your pump with some hoses and pump it in until you get the system to 12 psi

    Take that automatic air vent off (above the boiler to the right with orange handle valve). Get a piece of tubing that will fit over that nipple the vent is on and attach the tubing with a hose clamp and run the other end of the tubing back into your bucket.

    Now you need to get your circ pump running but don't let the boiler fire up. You will have to figure out how to do that. you cant fire the boiler until you have water in it and the system is bled

    Run the system circulator, crack the bleed valve with your tubing on it to let air out. If the pressure in the system drops below 12 psi add more glycol.

    Keep doing this until you get no bubbles out of the bleeder hose. then you should be ok
  • hot_rod
    hot_rod Member Posts: 19,281
    unless the circulator has a check valve, it will not be an easy purge. I'd add a Webstone valve that allows you to isolate and fill/ purge at on point. A good air separator would also help, glycol is hard to get entrained air out of.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • pecmsg
    pecmsg Member Posts: 3,888
    That relief piping needs to be 3/4" not 1/2"

    I hope your electric rates are real cheap!