Reply To: expansion tank

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In reply to message posted by Harold Kestenholz:
If the tank is a proper heating expansion tank with a diaphragm, only gas should come out of the needle valve on the bottom of the tank (and it shouldn’t be fooled with or there will not be the proper pressure to do the job.) Water indicates that the diaphragm is cracked and the tank needs replacement.

If you are talking about the small canister on the top of the air scoop above the tank, that is an air vent and water will come out now that there is no air in the system. Much water removal this way will lower water pressure and permit air to enter the system. Read the air purge procedure at for a fuller description of what is happening.

Harold your GREATTTTTTTTTTTTTT as Tony the “TIEGER” would say.

Now you can fully understand why I do not care for the trol tanks where a bladder can rupture and cause wacky out of control pressure.

At least with the older type all one had to do was drain it.

About the scraider valve on the so called automatic air eliminator this is why I use the Hoffman 75 or Spiro vent that removes even Micro bubbles rather then the beer can type cheaper model 77.

The schraider valve is prone to failure with any debris or even failure in the closed position due to rusting or particles blocking the orifice.

I am impressed how you guessed the system parts KEEP up the fantastic job your doing kind sir

Of course a lot of the heating *********** would never think of paying upwards of $100 for just an air removal device huh?


» This message has been edited by SylvanLMP on 29 March 2002

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