Automated purge for air compressor

[doojus]

Hi Guys,

I have an air compressor in an installation where it doesn't run very often and it tends to get a lot of water in the oil. It's a large compressor (7.5 hp, 120 gallons) and when I bought it I used a lot of air but right now it barely ever runs except to compensate for air loss in the lines once a day or so. I want to set up a purge valve on a timer so that once a month or so it'll purge air and force the compressor to run continuously for about 30 minutes or so. Is there a product like this that exists? I haven't been able to find anything for this specific purpose. Any help would be appreciated.

 

[Dad Was A Racer]

Here's what you need:

https://www.grainger.com/product/SP..._on_Your_Search-_-IDPPLARECS&cm_vc=IDPPLARECS

 

[doojus]

Here's what you need:

https://www.grainger.com/product/SP..._on_Your_Search-_-IDPPLARECS&cm_vc=IDPPLARECS

Thanks for the reply!

I actually saw this before I made my thread, and while it's basically the same principle of what I want, I don't think it's exactly perfect because it can only open its valve for a maximum of 10 seconds at 45 minute intervals. Basically something like what you posted except with a bit more flexibility and perhaps a digital controller would be perfect. I want something that'll let me force the compressor to run for 30+ minutes via air bleeding.

 

[LS6 Tommy]

Here's what you need:

https://www.grainger.com/product/SP..._on_Your_Search-_-IDPPLARECS&cm_vc=IDPPLARECS

I don't think that will dump enough air to make the compressor run long enough to warm the crankcase oil up enough to drive the moisture out. Even if it does, it'll make the compressor a real energy hog.

Tommy

 

[BillK]

How often do you actually use it ??? Personally I would turn it off when not in use. Then it will leak down on its own. I simply cannot fathom leaving an unused compressor on for a month at a time. I turn the one off at my business every night.

 

[doojus]

How often do you actually use it ??? Personally I would turn it off when not in use. Then it will leak down on its own. I simply cannot fathom leaving an unused compressor on for a month at a time. I turn the one off at my business every night.

It's used daily, just not in big enough quantities to warrant it running more than once or twice a day. It's a huge air compressor (120 gal, 7.5 hp, v4 pump) and it just doesn't run enough to get hot anymore. When I first bought it I did a lot of aluminum fabrication where running air grinders, cold guns, etc would make it run continuously a couple of times a week. Now it's relegated to pumping up tires and blowing off dirt and **** like that so I need a way to artificially exercise it on a schedule.

 

[log man]

FYI, The grainger device in this thread can be found as a generic part on Amazon for about 25 bucks.
https://www.amazon.com/dp/B01DIXZ8SY/?tag=atomicindus08-20

 

[dfiler2]

This might be a little redneck but you could use a 7 day programmable timer like this to run a mechanical timer like this to run a solenoid valve like this. The programmable time would be set to run the mechanical timer for one hour per day and the mechanical timer would run once every 24 days. You could play around and get it to run once every 30 days if you wanted.

 

[doojus]

This might be a little redneck but you could use a 7 day programmable timer like this to run a mechanical timer like this to run a solenoid valve like this. The programmable time would be set to run the mechanical timer for one hour per day and the mechanical timer would run once every 24 days. You could play around and get it to run once every 30 days if you wanted.

This looks like a good idea, if I can't find a ready-made device I might try it

 

[neilc]

I installed this one and have been very happy with it. It does allow you to control the duration and time between releases...

https://www.amazon.com/gp/product/B00S89W2KQ/?tag=atomicindus08-20

 

[ford33]

dfiler2 has it right.

Just buy a 7 day simple timer and connect to a relay or not depending on timer output to operate the normally closed solenoid valve. Time the valve open period to make the compressor run 30 minutes.

Maybe a lawn sprinkler timer would work but it would have to be connected to a 24vdc solenoid valve, I believe.

 

[doojus]

**** it, I'll make it myself

 

[HMCFab9]

Turn the compressor off & use up most of the air
Then open the drain valve & just let it run.

You don't need a fancy way to remove air when it's as simple as opening a ball valve.

 

[cvairwerks]

Put a tee in the main outlet with a ball valve vented outside. Open the ball valve first thing on one moring a week, then do your morning coffee and shop startup. Close the valve when it’s time to start operations.

 

[unslow1]

The shops I worked in we always bled the system every night. That pretty much took care of that problem. I still see shops doing that. You can always tell when the shop next door is shutting down. They have a big ball valve they open to bleed the system.

On mine I just haven't fixed a connection with a small leak. It serves the same purpose.

 

[BruceMc]

I want to set up a purge valve on a timer so that once a month or so it'll purge air and force the compressor to run continuously for about 30 minutes or so. Is there a product like this that exists? I haven't been able to find anything for this specific purpose. Any help would be appreciated.

Seems like an overly-complicated solution to a really simple task. If you just want to purge it once a month, why not put a reminder on your calendar? Or just get in the habit of purging it on the first day of the month?

 

[Dan in Pasadena]

Seems like an overly-complicated solution to a really simple task. If you just want to purge it once a month, why not put a reminder on your calendar? Or just get in the habit of purging it on the first day of the month?

^ THIS^

Geez, why assemble some kind of Rube Goldberg contraption OR spend hundreds of dollars?!

 

[doojus]

Simply put, my time is worth way more to me than the $90 it cost me to build something to do it for me. I had definitely considered doing it myself every month before I posted the thread

 

[nadogail]

My 20 gallon compressor, with a vertical tank, has a 1/4" ball valve connected to the bottom of the tank. The valve is extended out enough that I can operate the lever with my toe, allowing me to drain the condensate without bending over.

 

[Git]

Install a T and use a motorized ball valve

This one is powered by a simple 12-24v DC transformer - you probably have something laying around that would work. (f you don't have an outlet close by, it is a lot easier running a low voltage wire). This particular ball valve will close automatically when you cut the power

Lastly, you just need a simple programmable timer - something like this. Plug the timer in an outlet, plug the transformer into the timer

https://www.amazon.com/gp/product/B00SAFM5U0/?tag=atomicindus08-20

 

[Spareparts]

I put a solenoid valve on my tank drain with a ball valve on the outboard side of the drain just in case it fails to close. Powered the motor starter off my light switch for the shop. Turn the lights on it powers up the compressor and closes the drain, just the reverse when turning the lights off. Simple transformer to operate the drain valve. The only problem I have ever had in over 8 yrs was where the drain goes thru the wall got covered with snow. Well the neighbor's cat was there when when I turned the lights off, that was the fastest cat I ever seen, and that was the last time I ever seen it.

 

[metlmunchr]

Before you spend the money on an automated valve, just open enough valves in the system to keep the compressor running constantly and see how long it takes to drive the moisture out of the oil.

My 10hp rig that also gets intermittent use won't dry the oil with 8 hours of continuous running. I think the problem is most of the moisture partially separates and sinks to the bottom of the crankcase during periods of non-use, and when running, the crankcase area never gets hot enough to boil out the water.

Using a crankcase heater to keep the oil temp up all the time can go a long way in preventing condensation of moisture into the oil. Much easier to prevent it from getting in there than it is to get it out after it condenses. Some compressors are set up to accept an insertion type heater, and for those that aren't, a wrap around type heater will work as well.