Automatic condensate drain

[Miyaru]

I just acquired another Bauer K14:

Came from an offshore company, the salty sea wind has redesigned the colors.
Anyway, this will be a nice project for the next couple of months. One thing not present is an automatic condensate drain, and I'm to lazy to open the valves every 15 minutes for 6 to 10 seconds.

The original design has 1 normally-open solenoid that (electrically) closes during startup, and the pressure-build-up will close the drain valves from the subsequent stages. A timer will cut the power to that solenoid after 15 minutes for 6-10 seconds, causing the drain to empty and the pressure drop will cause the subsequent drains to empty as well.

Now my idea is to simply use solenoids after each drain, all normally-open and an Arduino that operates these solenoids every 15 minutes.

The price of SS304 solenoids has dropped so much, that building my own condensate drain is about 5 times cheaper than ordering the original mechanism. And the electronics are not a challenge, it's a simple timer and some relays.

Has anybody ever built this? Anything I should think of?

 

[windyairman]

Hi I have the the unit you want
taken off a old k14 unit

 

[eyeballgummy]

So what happened? I'm in the same boat with a K15. I have found 300 bar solenoids and can connect a timer. They have 1mm orifice size. Is this big enough to drain?

 

[Agro]

Now my idea is to simply use solenoids after each drain, all normally-open and an Arduino that operates these solenoids every 15 minutes.

Why normaly open? My solenoids are normaly closed and open every 10 min for 1 sec.

 

[Agro]

So what happened? I'm in the same boat with a K15. I have found 300 bar solenoids and can connect a timer. They have 1mm orifice size. Is this big enough to drain?

Yes, 1mm is enough. Perhaps your opening time must be 2 or 3 sec instead of my 1 sec, you must check this.

 

[Agro]

Has anybody ever built this? Anything I should think of?

Mine works as follows:
- 10 min closed
- Solenoid A opens for 1 sec
- 5 sec interval
- Solenoid B opens for 1 sec
- 10 min interval, closed
and so on.

I don't want both solenoids to open at the same time so I can check A and B are working.
This 1 sec works fine on my compressor, depends on cross sections. Perhaps you need 0.5 sec on A and 3 sec on B, check this.

I attached 1 big ballon to solenoids outlet to check the amount of air/oil/water coming out. About 6 lt is OK for me.

 

[InWay2Deep]

I built something similar for my compressor that didn't come with one. Instead of an Arduino I just used a timer,

https://www.aliexpress.us/item/3256803970295942.html

 

[TravisD]

Why normaly open? My solenoids are normaly closed and open every 10 min for 1 sec.

I always get NC and NO backwards..but on the factory ACD's on my Bauer, when the compressor shuts off it drops power to the ACD which means they open for a final time, preventing condensate from staying in the traps in-between runs. For me this is important since my fill station is in my unheated garage and it sometimes gets below freezing in the winter.

 

[grantmac]

Is there any issue with keeping a NO solenoid energized with that much duty cycle?

 

[Agro]

Is there any issue with keeping a NO solenoid energized with that much duty cycle?

No there is not. If you want TravisD's function a NO solenoid seems to best solution.