How do you drain a floor standing expansion tank? AMTROL Extrol model SX30V.

vynce82

How do you drain a floor standing expansion tank? I have AMTROL Extrol model SX30V. I just got one installed by plumber but system pressure is high - leaking to hold at 30psi.

It is a floor standing model with copper pipping going straight up to valve near ceiling height. I can isolate with the valve but how do I drain it to test the pre-charge pressure?

EBEBRATT-Ed

There is no way to drain it. Close the isolation valve and if there is a union between the tank and the valve loosen it (there will be some pressure). No union you will have to cut the pipe and when you put is back together put in a tee with a boiler drain on it and a union in the pipe. There are no drains on those tanks as far as I know

Tom_133

Typical installation we put a tee on the bottom instead of a 90 and add a drain, then you put the valve above the tee like in your situation. Draining is a snap then. If your installer didnt do that then it will be messy. In the past with flooded tanks I open a drain on the system and blow air in the expansion tank with a compressor. As long as the tank is bad it pushes all the water out and makes taking that bad boy down simpler.

HVACNUT

There should have been a drain installed during the installation. 
Did it change from a steel compression tank to the diagram tank? If so, is there now a means of automatic air elimination?
If cold pressure was set to 12 psi, what happened to make the pressure rise?

Jamie Hall

HVACNUT said:

There should have been a drain installed during the installation. 
Did it change from a steel compression tank to the diagram tank? If so, is there now a means of automatic air elimination?
If cold pressure was set to 12 psi, what happened to make the pressure rise?

It's that last question I'm wondering about. Expansion tanks don't add pressure, they just control it. How did the system pressure get that high? Bad pressure reducing/automatic feed valve? Leaking manual fill?

mattmia2

Does it have a tankless coil or indirect water heater to make domestic hot water?