Homemade Auto compressor drain

[fixit]

In my other life a a corporate maintenance engineer we had a constant water problem in our compressor operation. Each plant had no less than 3500 (yes 3500) horsepower of compressors on line at all times 24-7-365. I found the best auto drain was a 3/8 " motorized ball valve with a built in timer, they could be set for various schedule of operation & had a test switch for manual operation. On schedule the valve would slowly rotate open & close. At 3/8 inch dia it never plugged up. For smaller air receiver we used a plug with a small orifice to reduce the pressure drop but most of the receivers were 6 ft dia X 15 to 20 ft long. Believe me I tested MANY no fail drains that failed.

fixit

 

[tq60]

If you have an unloader valve it can be used to operate a sprinkler type of valve where the vented air operates the release.

That is how the automatic ones work in that they operate the tank drain every time the compressor cycles.

Our compressor came with it and there is very little in the way of parts so it cannot cost much to simply buy one.



Sent from my SAMSUNG-SGH-I337Z using Tapatalk

 

[JPigg55]

Here's one from Harbor Freight for $10 with a Youtube video of how a guy installed it.

https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html

 

[woodchucker]

Here's one from Harbor Freight for $10 with a Youtube video of how a guy installed it.

https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html

That unit does not work with my compressor, or any of the 3 compressors I have. And it is prone to failure. It has an extremely high failure rate if you read the reviews.

 

[Bob Korves]

If you have an unloader valve it can be used to operate a sprinkler type of valve where the vented air operates the release.

That is how the automatic ones work in that they operate the tank drain every time the compressor cycles.

Our compressor came with it and there is very little in the way of parts so it cannot cost much to simply buy one.



Sent from my SAMSUNG-SGH-I337Z using Tapatalk

That is how the big truck ones work. The unloader initiates the drain cycle, and the tank drains the water. The cycle interval is related to compressor cycling, that is, it cycles each time the compressor turns off, not some random setting on a clock timer. Very simple and reliable system, and easily repaired should it ever fail, which they nearly never do. Some have heaters, but the heaters are 12 or 24 volts.

 

[Terrywerm]

I have one of the drain valves from Harbor Freight, and yes, it does work, but it drains so little water each time that I still have to manually drain the tank on a regular basis, at least during the summer months. During the winter the air is dry enough that I get very little moisture in the tank.