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Compressor automatic drains

?? There's a test button right on it, push that at the end of the day.
I was lazy and put my auto drain valve down on the floor almost under the tank. Too hard for these old bones to lean down there to push a button and worry the compressor might fire up while I am half way balanced.
Bill D
 
I have installed/modified several compressed air systems where operation was 24/7/365.25 and even a single drop of moisture at the air use point was a real problem. They usually had dual compressors with one tank and serious drying equipment after that.

I always used a manual drain valve that was mounted on a horizontal length of pipe to make it easier to drain the tank. It went to a drain hose which could be clear tubing so you could see that it did drain.

But my best tip is that I always tried to draw the air for the compressors' intakes from an air conditioned space. I simply ran a large diameter, galvanized pipe from that space to the intakes of the compressors. A muffler can be fitted to the end of that pipe if the noise is objectionable.

In my present, small, garage shop the compressor is in the air conditioned space of a storage room off the main shop. It is on a switch and I only run it when I actually need air. I still use a manual drain and I see little to no water when I drain it.

Not having much water in the tank has another advantage in that rust should be occurring at a very slow rate.

I did buy an automatic drain kit which functions when the pressure goes to zero. I haven't installed it yet. Too many projects: too little time.
 
I have an electric one, it works great. Well, it did until one year my shop flooded, about 4" of water, enough to swamp the drain. As I have been too lazy to pull it and figure it out, I just hit the manual switch on it and it drains, so I have to remember to do that every once in a while, depending on use. But it WOULD work if I fixed whatever shorted in the flood...
Mine has a hose that goes straight thru the wall and outside, so I dont hear it much when its draining.
Its easy enough to see if you have GFCI breaker on the stove- it would be in the main panel, and it would be clearly labeled GFCI. Unlikely, as they are a hundred bucks and up for a 50 amp, double or triple a plain one. Usually only see them on appliances involving water, not stoves.
And even then, pulling a 120 line to the drain shouldnt affect the GFCI.
 
I used two 120v regular 1/4 inch solenoid valves, one at the bottom of tank and one 30 feet down the main line with a slope. Found a timer, unfortunately on Amazon. The timer is both an on timer and an off timer. Compressor kicks on, valves open for 4 seconds. If the compressor runs for more than 4 minutes, it cycles again for 4 seconds. the off/on times are adjustable. Timer was $10, bought two for a spare. Works very well and you're using easily found components rather than a system. FWIW
 
Don't buy from Amazon. They are in litigation now for being a monopoly. Besides that thing is a cheap import.
I totally agree. But most of the places I go that type (those types) of import tank drains are featured. I had to look for quite awhile to find a single auto drain unit over $100. I have two units already. Mine are made by Lewis Systems out of Greensboro, NC and look a lot like the one in this image:

PosiDrain.jpg


Plumbing it into my air tank's central drain is no problem. It's just about what's a clean way to mount the thing and where to run the effluent line.
 
My automatic drain is my hand.......when i turn the compressor off at the end of the day , I reach
down, flip open a ball valve and 5 sec later tank is drained. :D
Then I close the "tank to system" ball valve so those pesky tiny leaks don't drain the tank overnight.
No electric, no clogging no cost.........
I have got into the habit of turning it off overnight just in case a hose breaks etc. and causes the pump to run all night....
 
My automatic drain is my hand.......when i turn the compressor off at the end of the day , I reach
down, flip open a ball valve and 5 sec later tank is drained. :D
Then I close the "tank to system" ball valve so those pesky tiny leaks don't drain the tank overnight.
No electric, no clogging no cost.........
I have got into the habit of turning it off overnight just in case a hose breaks etc. and causes the pump to run all night....
I've got all my condensate sources plumbed to individual drain valves on a manifold. The nightly routine is to shut off both compressors, shut off the drier, then drain each tank (two storage tanks, backup compressor 80 gallon tank, and the regulator / separator bowl) individually.

If anything changes with my air system, I'll know it instantly.
 
I'm gone 3 months out of the year, and I leave my compressor powered up so the people living in our house can use it to inflate tires. Auto drain is a must.
 
I've done a small blasting session and the pneumatic drain seems to work well. I set it to its slowest cycle, which is still faster than i probably need, but is slow enough to not pose any problems. Added bonus is that it drains the tank empty, which in turn drains my Milton air dryer/regulator combo.
 
My compressor is 220V and has two drains.

The one on the tank has an electric adjustable timer. From 30 seconds up to 30 minutes.

The filter water separator one is mechanical and drains every time the air pressure drops in the top of the filter which lifts open the drain valve in the bottom. It only opens for a fraction of a second.

Both have hoses so you can direct the water to a jar.
 
I have an electric model on my 20 hp compressor. It works well but the built in timer has a limited range of cycle times so I added a programmable timer and plugged the auto drain into that.
Off the shelf it would drain every 30 minutes with an adjustable 2 to 15 second blast. I initially had it draining once every day and had some problems with the filter clogging and the valve sticking shut. Just needed to clean it and re-install and then made it drain twice per day which has solved the problem.
I run this compressor for my blast cabinet and all other shop needs so it sometimes runs a lot and sometimes not for days. The main wet tank is 120 gallon and then the air goes through a refrigerated dryer into the 120 gallon dry tank which is then plumbed underground into the shop. Never have a drop of water in the system. The dryer comes on automatically with a small amount of air flow (expensive flow switch) and then cycles for 15 minutes. Not a simple system but it works well and my air dryer only runs as needed. The dealer said it was supposed to run all the time which I thought was ridiculous and it should have had a built in on/off on demand. Especially for a $4000 dryer, I thought Kaiser would have figured that out.
Compressing air is expensive, drying it adds to the cost so keeping the energy usage down is worthwhile. Plus it should extend the life of the dryer.
ps, I never completely drain the system.
 
I have a quincy qmat-01 for 6+ years now with no issues. Zero loss, moisture sensing:
 
I use an extension from the storage tank to an intermediate zone that can collect water and makes for better access to valve handles and controls.
The important thing is that no water pool is collecting in the tank. The water collects in the intermediate copper pipe. The Asco valve operates whenever
I want and the manual valve is for the water that condenses in the tank a few hours later when the air cools. When you do a manual drain op and come back
later you will have a bit more to drain. And all this was from the past. Now I use a 50' coil of copper to condense the water out before it enters the tank.

DSC_1538.JPG
 
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Wilkerson makes an automatic compressor tank drain that operates off of pressure differential between when the compressor kicks on versus off. I ran one on my compressors and it lasted around 15 years before it had to be rebuilt.

Grainger's sells them.
 
I've got an Asco automatic electric drain, too. I only run the compressor perhaps one day a week, but it's worked flawlessly for 13 years now. It's set to drain for 15 seconds every 45 minutes. I have the exhaust running through my wall to the outside because it's so noisy. Sometimes I'm outside with a visitor when it goes off and scares the daylights out of them!

Oh, yea, if you don't want to split the 220v, you can install a 220 - 110 stepdown transformer very easily.
 
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