auto tank drain valve continuously leaking - check valve?

I have a dayton speed air 1WD63 7.5 hp compressor. The compressor will fill properly but when the motor stops then the auto tank drain valve will release all pressure till the motor kicks back in. Once the motor turns back on then the valve will shut off. The valve only opens when the motor is not running. What can I do to stop this from happening? My motor is running overtime to keep up with the air loss.

Jason

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Bill says...

Jason, when you say the "auto tank drain valve" are you referring to the "unloader valve" that's often attached to the pressure switch?

If that is the case, then the issue is likely with your tank check valve.

Please click the Valve link from the nav bar, and then the Check Valve link for specifics. You might as well have a look at the Unloader Valve page too, for general info.

I believe if you fix the leak in your check valve, your compressor problem will be fixed too.

If it is not the unloader valve you are referring to, what valve is it? Please post your answer as a comment on this thread, OK?

Cheers,

Bill




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auto tank drain valve continuously leaking - check valve?

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Nov 18, 2010
 response to auto tank drain valve continuously leaking
by: jason

The valve has a diaphragm in it. There is a line coming from the bottom of the tank with pressure on it at all times. This line attached to the bottom of the valve. At the top of the south is another line that goes to the unloader valve. When the unloader valve is tripped the pressure from the line trips the diaphragm calling all the air to leak out. The unloader valve is activated until the motor turns on then shuts the unloader valve off.

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Bill says...

Jason, if the unloader valve is working properly, then your compressor will run satisfactorily.

If the auto tank drain valve is leaking continuously, causing the tank to drain and your compressor to restart unnecessarily, then, as far as I'm concerned, while you resolve the problem, put a manual valve in the line to the auto drain, and shut it off.

Then, you can at least use the compressor while rectifying the problem.

While an auto drain is nice, I prefer the electric ones that open for a few seconds every 15 minutes or so (this is normally adjustable) to keep the tank empty of water.

The diaphragm drain valve quite possible has some debris in it that is preventing the internal spring (or internal air pressure from the tank) from closing it.

Good luck. Please keep me posted. I took a look at the overall concept, but couldn't find details on the operation of this unit.

Cheers,

Bill

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