Northern Tools seems to have a variety in their Air Compressor Accessories. I have a simple line filter (leaving the tank) that I can see the moister and filter element in. It also has a schrader valve on the bottom to bleed the clear filter bowl. Due to condensation, I try to bleed my compressor's tank yearly or before any serious painting or finishing. The amount of water I would find in the tank told I needed some help to save the bottom. I added a galvanized elbow and pipe below the tank to take on the water and as an easy access to drain. Good luck! loger

Loger, you should drain that tank at least once a month. When water lays in the tank for long periods that's when the tank starts rusting and getting thinner.
Mike

Thanks mla2ofus, I know More Would Be Better! I purchased the 1 HP AC Compressor from Sears in 1972 and it showed to have a pin-hole 2-3 years later. I put a self-tapping screw and a "O-Ring" in that hole and have not found another or signs of weakness since. I feel the grease (mixed fairly well) in the water and TX Heat has helped to preserve it. Plus, at one point I was told to leave a pin-hole for it to drain itself, and I did for years. I turn it On/Off with a H/D timer 0-12 Hrs as my switch vs it coming on later. BUT! I have had a new replacement tank stored since about 1975. I might need to check it after all these years. LOL! loger

I have a combination Filter Separator / Oiler on my Atlas Copco Compressor . Although I still routinely blowdown my tank to eliminate any residual debris monthly. If your compressor is stored within a none heated building condensation accumulation can be more of a headache , requiring more dedicated mtce.

Thanks for your opinions. I Googled 'Water separators'
and found lots of them for sale. Some for less than $10,
and some over $1,000. I just wondered if anyone
had one they were very happy with and what it was.
I just got a new Rolair compressor, (what a gorgeous
piece of equipment), and I wanted to get it set up
right from the get-go.

As I advised my application requires due dilligence (thermal cycles) since my garage is not heated at all times . I therfore ensure to buy the combination water separator � filter and auto adjusatible oil station when I purchased the unit . I believe the adder was $75 for the 3 stage unit . Works great and has over 5 yrs on the components . Sizing was critical for proper cfm and undue back pressure within the system . Atlas Rep did all the sizing according for my application .