Air Compressor Drain

[Augusto Orosco]

The drain cock in my PC Pancake compressor doesn't close tightly anymore, forcing the compressor to cycle way too frequently.

I always hated the thing; it's a pain to reach and I always end up turning it the wrong way. So, I decided it's time to replace it with a ball valve.

I have a silly related question though, but I found some conflicting information so I thought I wuold ask here for some opinions:

At the end of the day, do you drain ALL the air of your compressor, or just enough to expell the moisture? I always drain every bit of air at the end of a session, but I don't know if this is overkill.

What made me think of this was the instructions on those automatic drain kits at HF (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=46960). The manual says that the drain is activated everytime the motor turns on and off, releasing the moisture. If that's how they work, then it must be that they only let a little air out every time, and never drain the whole tank.

Thoughts?

[Dan Friedrichs]

Yep, just let out the water. No need to drain the whole tank. The water just condenses when the air cools in the tank (the pump heated it up). So once it's in the tank for a little while, no more water should condense out of it.

[Don Jarvie]

Cheap fix is to just replace the valve with a ball valve.

Do a google search and there are instructions on how to do it.

[Don Whitten]

Finally had to replace mine valve last October on my 6x60 after 15 yrs of service, just got to remember it isn't righty tighty.

[Chip Lindley]

A $10 ball valve will make compressor life Wonderful! A quick fix by adding a 90deg nipple if the drain hole is hidden down beneath the tank, as on every compressor I have ever owned!

Even the big 60gal. vertical Quincy had a butterfly cock hidden inside the base. I replaced it with a 90deg. nipple and length of 1/4" iron pipe. For a time I also had a nice ball cock outside the base, but tired of *remembering* to drain the tank.

I found a really nice Ingersol Rand auto-drain on eBay at a nice price. The exhaust can be set for frequency and duration, and will do it's thing as long as the compressor breaker is ON.

[Augusto Orosco]

Yep, just let out the water. No need to drain the whole tank. The water just condenses when the air cools in the tank (the pump heated it up). So once it's in the tank for a little while, no more water should condense out of it.

Thanks, Dan. I am glad to hear that draining the whole tank was overkill!


Cheap fix is to just replace the valve with a ball valve.

Do a google search and there are instructions on how to do it.

Thanks, Don. That is my plan. It's a pretty simple mod. I only mentioned the HF unit because that's how I get to wonder about just how much to drain. A ball valve looks

[Steve Clardy]

A $10 ball valve will make compressor life Wonderful! A quick fix by adding a 90deg nipple if the drain hole is hidden down beneath the tank, as on every compressor I have ever owned!

Even the big 60gal. vertical Quincy had a butterfly cock hidden inside the base. I replaced it with a 90deg. nipple and length of 1/4" iron pipe. For a time I also had a nice ball cock outside the base, but tired of *remembering* to drain the tank.

I found a really nice Ingersol Rand auto-drain on eBay at a nice price. The exhaust can be set for frequency and duration, and will do it's thing as long as the compressor breaker is ON.


Yep. Did the same here. $200.00 list price valve purchased on Ebay for $60.00

I have mine set to release for 3-4 seconds every hour.

[Josiah Bartlett]

The other good thing about adding an elbow, a length of pipe, and a ball valve, is that all the water collects inside the pipe instead of inside the tank. Its a lot cheaper to replace a pipe nipple than a tank.

I just burp the water out of mine as well. I have a horizontal 30 gallon Quincy with an ASME tank.

[Bob Wingard]

WILKERSON makes an auto-drain valve that works very well for around $60-$65. It opens for a few seconds every time the compressor shuts down after filling, and again anytime there is a drop in pressure of 10psi or more.

[Jim Becker]

You can almost always replace those OEM drain cocks with something more usable made from a few parts out of the plumbing section of your local store.

I use an IR automatic drain system on my compressor, but would certainly drain the moisture on a regular basis if I didn't have that setup.

[Tony Bilello]

I always hated the thing; it's a pain to reach and I always end up turning it the wrong way. So, I decided it's time to replace it with a ball valve. I havent changed mine to a ball valve yet. I'm sure it will be much easier on the fingers. Besides, I hate lying down on cold concrete to reach under there. Tony B
At the end of the day, do you drain ALL the air of your compressor, or just enough to expell the moisture? I always drain every bit of air at the end of a session, but I don't know if this is overkill. I drain mine completely every day of high humidity. If we have a lower than usual amount of humidity, I will only drain it till no more moisture comes out. I might drain my moisture filters several times a day if we have a high humidity. Tony B
What made me think of this was the instructions on those automatic drain kits at HF (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=46960). There are very few things that I bought at Harbor Freight that did not fail. I would not trust it. Tony B
Thoughts?

Ever since I started woodworking, I have always lived in very humid areas. I also drain my tank if I think I wont be in the shop for several days. I am not worried about the tank rotting out because I havent heard of that happening yet. I spray a lot and my biggest concern is moisture in the tank or the lines. It may be overkill, I'm not sure but it only takes a few minutes for the tank to refill itaself next time I use it.