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Air stem for pre-charge adjustment on Amtrol Extrol 30

jsilks Member Posts: 2
I know nothing about water/heating system and should not have been messing around with this, BUT...

I have been hearing a loud gurggling sound in the water system along with some loud banging of what I am guessing are the pipes. I was poking around a little and found a air tank above the boiler with Amtrol Extrol 30 on it. Anyway, not knowing what it was I reached up and pressed the valve release (much like a bike tire) and let some air out. Smelled absolutely horrible by the way. Anyway, I did some research online and now realize I may have messed up the pre-charge of the system, is that correct? The house was built in 1996 and perhaps the tank has been in the system since that time...not sure? I bought the place in 2005. Any ideas what i should do now - buy a new tank, re-pressurize this tank? Why am I hearing sall these new noises in my system?



  • STEVEusaPA
    STEVEusaPA Member Posts: 5,454
    2 separate issues.

    1. Extrol tank.  You (or a service tech) will have to isolate the tank from the system (hopefully you have a valve there) & remove the tank.  If you dont have a way to isolate, you're going to have to do alot of system draining.  Then check the charge with a tire pressure gauge, and re-charge as necessary, to get it back to the proper psi. You might as well wait and see if its holding its charge also. And if there wasnt a valve to isolate it, put one in, like the webstone expansion tank pro service valve.  Now obviously its more involved then that. Like reconnecting it properly, adding more water to the system, purging system of air, etc.

    2. Banging pipes/gurgling sound.  You'll have to be a little more descriptive.  Could be a number of things.  Gurgling--not enough water in the system, or something is air bound, etc.  Banging?  You really have to be there and see where it's banging (not so easy), when it's banging, to determine why it's banging.  Hard to diagnose on the fly.

    Best bet, time to get someone out there to take care of your tank, and get everything straightened out.
  • jsilks
    jsilks Member Posts: 2
    Gurgling and banging

    The gurgling sounds like air bubbling up in a natural spring - just what it reminds me of. I hear it most often in the early morning when sitting in my office, which is on the 2nd floor of my 2 story home. There are two thermostats in my house, one upstairs and one downstairs so I am guessing that means there are two closed loop systems running through my boiler???

    There is a valve right where the tank is connected.

    The banging sounds like it is in the floor/wall where the pipes go into the floor/wall from the boiler. Somewhere up in there - hidden from plain sight.

    I see you are from PA - any chance you are near state college and have a service business???

    Thnx again
  • icesailor
    icesailor Member Posts: 7,265

    If you don't own a air compressor or an air storage tank for filling tires, call a pro.

    If you have the above, here's another way.

    Locate the Pressure Reducing Valve that fills the boiler and maintains the system. If you don't know where it is or can't find it, call a Pro.

    If you find it, turn it off. Turn off the power to the boiler.

    Connect a hose that will drain the boiler to a convenient place.

    Locate the pressure and temperature gauge on the boiler. If you can't find it, call a pro. If you find it, note the pressure reading on the gauge. Note whatever it is. It should show between 12# and 15# PSIG. Note the pressure. If you can't understand what you see, call a Pro.

    Open the drain on the bottom of the boiler. If you hear water running into the boiler, you don't have the fill valve. Stop and call a Pro.

    The water should run out of the boiler for a very short amount of time and stop. If you see any vents hissing on the boiler that look like small cans, with caps on the top, close the caps and stop the hissing.

    Note the pressure on the gauge. Did it drop to zero? If it did, quickly take the cap off the bottom of the #30 Extrol tank and see what the pressure is. It should be between 10# and 12# pressure on a tire gauge. If it is, the pressure is OK. If it isn't, add pressure to the fitting until you get 10 to 12 # PSIG.

    Close the drain for the hose. Open the valve to the boiler fill valve. Do you hear water flowing into the boiler? If you don't, you may need to change the boiler fill valve. If you hear water filling the boiler, leave it alone and see how high the pressure goes. Open the caps on the air vents. If they leak water, close them.

    If you have gotten this far successfully, you may have the skills to continue as needed.

    If the pressure in the system after a period (say one hour),  doesn't get to 10# or 12#, there is a way to add more water pressure but the valve may not work after that. I suggest changing the valve to a new one. If it is broken and leaks by, it will be a PITA. I usually change them so I don't have to go back.

    The fact that you get air out of the #30 Extrol tank says that the tank is probably intact. If you get water out of the bleeder valve, call a Pro. Changing the tank when full of water can be hazardous to your safety. It is heavy and difficult to unscrew and let down without dropping it on your foot or anything below it. Call a Pro.

    Unless you let a very large amount of air out of the tank, if it is around 10#, you are Ok. You can add air to bring it up to specs. I would leave it at no more than 12#. I usually leave the system pressure set at 18#.

    I have NEVER taken a Extrol tank down to check the pressure. I always do it as I described and it will tell me anything I need to know.  
  • STEVEusaPA
    STEVEusaPA Member Posts: 5,454
    to quickly answer your questions......

    Yes I own a full service oil company.  Unfortunately, I'm right outside Philadelphia, so not very close.  If you have oil, I would hope that your oil company could help you.  If you have gas, I would look for an HVAC company that specializes in hydronics, or a plumber who really knows hydronics, not just a plumber who added " & heating" onto the side of his van because he can solder pipes. 

    Either oil or gas, you should have a service company that will come out every year so service the system.

    What icesailor recommends, is the better way to accomplish your goals, but I think it's not the best way a homeowner should approach your problem.  There's too many opportunites to get yourself into more trouble if things dont go exactly as planned--i.e., the valves dont hold, boiler drain starts leaking, the prv or water feed needs to be replaced, etc.
  • walnuts
    walnuts Member Posts: 21
    system pressure

    I agree with almost everything....      system pressure should be set to the equivalent expanstion tank psi  exactly   12=12    or 18=18
  • icesailor
    icesailor Member Posts: 7,265
    Getting Help:

    Which is why I said to call a "Professional" after every questiion.
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