What's new
What's new

Air Compressor Cooler--Worth The Cost?

munruh

Hot Rolled
Joined
Jan 3, 2011
Location
Kansas
Ok, I have a quote here for an air compressor cooler. It seems high. At this location we have been running over 8 years. There are 3 CNCs here. I do battle having water in the lines especially in the humid summer. I do have a couple filters in the line and that helps some. The compressor has a radiator thingy on it which was supposed to help, but doesn't. It will be over $1,500 by the time I have it installed correctly. I'll have the fellow that does maintenance for me do it. Will it be worth that? Do I just not know what I'm missing out on? Kind of like didn't have a water softener in the house for years and now wouldn't do without one?
 
If dimensioned properly it will get out all the moisture
I was advised to install it between the compressor and the storage tank
That way you never have a airflow bigger as the capacity of the compressor

Peter
 
Ok, I have a quote here for an air compressor cooler. It seems high. At this location we have been running over 8 years. There are 3 CNCs here. I do battle having water in the lines especially in the humid summer. I do have a couple filters in the line and that helps some. The compressor has a radiator thingy on it which was supposed to help, but doesn't. It will be over $1,500 by the time I have it installed correctly. I'll have the fellow that does maintenance for me do it. Will it be worth that? Do I just not know what I'm missing out on? Kind of like didn't have a water softener in the house for years and now wouldn't do without one?

I have a Doosan that continually runs air through the spindle as part of the spindle lubrication ,if any your machines has a similar set up you could ask your self what would be the cost of a spindle replacement. The cost of the dryer is going to be a lot less.
 
Yes

If budget is the issue


Compressed Air Dryer - Save on this Compressed Air Dryer

ran one of these for years and still own it.

Had one of those. It lasted about 5 years, it was finicky though, and it would freeze up
every so often.

To the OP, YEAH!!! You need dry air. You may not see it today or tomorrow, but
when the air operated stuff in your CNC machines starts rusting... $1500 is going
to look like a bargain.

When you plumb it in, make sure you put in a bypass. I've learned this lesson twice,
in 2 different shops. Everything shut down for hours and hours because the damn thing
freezes up. Or you need to shut the entire shop down and drain all the air to do some
maintenance.

I would also make sure that you have cooled and removed as much water as you could before
you got to the air dryer, then it has less work to do.

Right now I'm needing a new air dryer, I'm just going to get an old refrigerator, and
run a big coil of copper through it. If the frig dies, I'll just run down to the thrift
store and get another one for $100. Air dryers are expensive, and there really isn't a
whole heck of a lot to 'em. You're just making stuff cold.
 
If dimensioned properly it will get out all the moisture
I was advised to install it between the compressor and the storage tank
That way you never have a airflow bigger as the capacity of the compressor

Peter

I like your idea Peter. In theory is sounds like it would keep the water out of the tank, does it?
 
I like your idea Peter. In theory is sounds like it would keep the water out of the tank, does it?


The issue is that in this configuration it is impossible to get a airflow bigger as compressor capacity
So with a dryer the same capacity you never have a too big of a airflow over the dryer resulting in moisture in the system
If you hook it up after the tank there is a big chance of short periods of too big a airflow over the dryer
Additional advantige is no moisture in the tank

Peter
 
Right now I'm needing a new air dryer, I'm just going to get an old refrigerator, and
run a big coil of copper through it. If the frig dies, I'll just run down to the thrift
store and get another one for $100. Air dryers are expensive, and there really isn't a
whole heck of a lot to 'em. You're just making stuff cold.

good stuff Bob, BUT... you do obviously need to actually drain out the water once it condenses. a manifold or tank at the bottom of multiple runs of copper (perhaps with an auto drain valve)? AND of course, all pipes and connections have to be good for the pressure.. AND then would need a "U" stamp certification to pass some local code and insurance requirements.... uh.. ok, maybe the 1500 isn't so bad after all!!

another idea to reuse consumer goods for this is to connect a small window AC unit BEFORE the compressor, that at least could bring your dew point down to 35-45 deg to start with. that wouldn't do anything for you generally if it's below freezing outside, or you live in the desert, but on humid days or in tropical locals, could be helpful
 
NEVER FORGET: The gas laws that you learned in HS Chem are your best friends for compressed air delivery. Store air at the highest pressure possible and use at the lowest pressure possible. That little trick alone will do wonders at extracting moisture.

And why do you care? A refrigerated dryer will only give you about 40 F dew point. So when you've got 37 degree ambient and 90% relative humidity at the compressor inlet the refrigerated dryer is near useless.

Ideally a long metallic run from the compressor head to the refrigerated dryer followed by a dry receiver at as high a standing pressure as the dryer will support.
 
NEVER FORGET: The gas laws that you learned in HS Chem are your best friends for compressed air delivery. Store air at the highest pressure possible and use at the lowest pressure possible. That little trick alone will do wonders at extracting moisture.

I would add store it at the highest possible pressure and lowest possible temperature. For that reason, put the cooler between the compressor and the tank.
 
In Kansas set up the compressor to intake outside air in winter, the colder the better. Even better if the compressor pump is outside as well. In summer you may want to intake air from a underground pipe that is cooler then the air
Bill D
 
If it's a two-stage compressor, the radiator decreases the amount of power required to compress the air.

One technique I've seen to reduce the load on the air dryer is to run the air through a decent length of copper pipe before it gets to the dryer.
 
On my 2 stage compressor I added a small radiator with a fan between the compressor and tank. The idea was to drop the temp to ambient before it goes into the tank, the separator after the radiator catches an extreme amount of moisture before the air gets to the tank. It worked fairly well but later added a refrigerated separator inside and it now catches what is left of the moisture. The compressor is outside because of the noise and heat. If I had to do it over I would do the same in that order.
Added thought, the refrigerated dryer is inside and dries the air before it goes to the pressure regulator.
 
Bringing the compressed air from north of 200f to ambient before the storage tank is a good idea but IME it only good enough if ambient is below 65f, above 80f and I start noticing a little water vapor in my blowgun when it shuts off. I am usually around 40-60% relative humidity outside. What makes the biggest difference is taking your compressed air below ambient. Once I ran my air through a tub of water I almost stopped getting any in my storage tank and absolutely never get any in my shop. I haven't seen a drop of water in my shop trap since I did this around 5 years ago. What is missing in the photo is the box fan on the compressor mounted coil and the auto drain trap between the water bath and storage tank. In hindsight I would use 15' of copper to bring the air to ambient and maybe 5'-10' in the water bath, it doesn't take much.

Sure the HHSP setup might not work for you but the mechanics are the same. You really need two radiators with one in water to work well enough to avoid a dryer.


C-1.jpg
 
I used the linked drier for a number of years with several 5hp 80 gallon compressors, in an under air conditioned space here in the NE. We never ever had water in lines that were used. A small amount might collect in an unused drop after several years. The advantage to this setup is cost, first, and the use of the compressor tank as a bulk water separator.

I now have a ZEK drier between the compressor and a 400 gallon tank. It has been about 4 years and there has never been a drop of water in the tank.

Not a drop.

Worries about refrigerated driers not working in certain situations are either entirely theoretical, or for air drying needs that exceed machine shop specs.
 








 
Back
Top