How do these auto drains work?

[Bottlecapdigger]

I just got a new to me air compressor and I've been going over it cleaning and checking it over. I ended draining out about 2 gallons of water which led me to believe that this auto drain was not working. I took it apart and cleaned it up was coated inside with rusty water. There's a float inside which would lift up when it gets full of water. But when the float is down all the way it doesn't seem to seal anything off? Am I missing something here? The brass fitting on the end has a manual button on it which will let it drain out. Is the other black thing with the float just an indicator and still needs to be drained manually? I could maybe just google it, but the experts are all right here on this site. Thanks BCD

 

[The Tool Tyrant]

I'm not familiar with that particular set-up, but I believe the 'black' filter is upside down?

 

[Bottlecapdigger]

No Im pretty sure this is the correct way if i take the black plastic guard off the bowl the writing is the right side up. Other wise the writing would be upside down. But why have the guard over the bowl it restricts the view of the water level so much you cant see the water level anyway?
Also the copper line on the top goes to the tank, so that way the pressure would be equal on both sides of the float. Im begining to think this is a manual drain. the black unit is only a visual indicator to let you know when there is water in the bottom of the tank
Seems like a lot of junk a person dosen"t need.

 

[kythri]

I was going to say the same thing, that looks upside down.

The line you mentioned goes to the tank is what I've always seen as the actual drain on any kind of compressor water trap.

 

[MacMcMacmac]

The top line is a vent back to the tank so you don't get a high pressure build up which would prevent water from draining from the tank. Think piston rising in a cylinder. If that line is plugged that could cause the drain not to operate.

The cannister is the right way up.

The push button is a manual override.

There should be a screen in the brass egg, that may be full of rust and sludge.

Other than that, I never really took one apart, but I have seen many on HVAC compressors.

That DeVilbiss 44642 pump is a very high quality unit. The only downside is the iron HP piston can sometimes gall on the wristpins, leading to lots of slop and knocking.

Google DrainView products.

 

[Bottlecapdigger]

Thanks for the info, I'll take the egg apart and clean it as well, and the pump I'm going to change the oil and make sure it's at the proper level. What would be the best oil to use in it? Thanks bcd.

 

[sberry]

Synthetic compressor oil. A change is likely good for the life of the unit.

 

[Gittgo]

Toss that filter out. It's downside up to begin with and a new shiny blue cheapo Campbell is $20-30. If you can put your hands on a Chinese USB inspection camera thingy stick it in the tank and make sure the pitting isnt too heavy.
You want no part of this

 

[sberry]

That vid has been posted a million times. **** does happen but that is so super rare its almost a dis service to show it.
How does the auto drain work? Obviously not all that well,,, I like a common ball valve and a hose plumbed out, when I read a thread I go over once in a while and crack the valve.
Cope who posts here knew someone it happened to, this is the only other injury I even had heard of and the only other failed tanks I even know about were from internet over 20 years.

 

[Bottlecapdigger]

That's what I'm going to do , take all the stuff off and just leave the ball valve and ya just open it once in a while. BCD.

 

[sberry]

I have 3 vessels. a valve on each but plumbed to a common drain hose that runs thru the wall. All this stuff is instinct to me, if I run it a lot in humid then I open it. If I don't use it then am not so fussy. I had scrapped something and only had to make 1 flare to do it. Found every piece from old copper water line.