I am building a compressed air system for my workshop around a 5hp(3.7kW) scroll compressor module out of an industrial skid-mounted system. Since the compressor module is not configured for mounting on top of a tank, it will be mounted separately. This opens up a lot of options for tank placement. I am considering placing the tank(s) outside the shop to save floor space. The compressor will be inside so that it intakes dryer air from the climate controlled space and the compressed output will go through a radiator and water separator before entering the tank, regardless of where the tank is located.

I don't really understand how dew point works, so this is my question: will the tank(s) sitting out in the sun result in more entrained water in the compressed output? Less water? Or no difference?

 

Put the tank (air intake) where the air has the lowest humidify. Inside probably.

 

It almost doesn't matter where the Tank is placed.
But if You have to pick one, outside, ( hotter ), is probably slightly better.
What really matters is how well the Air was dehumidified BEFORE it went into the Tank.

To some small degree, Air stored outside in the heat will initially "act-like" it contains less Water,
until the Temps of the released, pressurized-Air comes down to the Interior-Room-Temps,
then any remaining moisture will tend to drop-out of the Air and show-up as Water-Droplets.
Having the Storage-Tank inside will just make the Air appear to contain slightly more moisture,
when in reality, it is exactly the same.

The amount of Water contained in the Compressed-Air is determined by
the efficiency of the Air-Dryer, and to a much lesser degree, the Temperature of the Stored-Air.

If You are using the Air for Spray-Painting, run the Air through a second De-Humidifier before use.
If You are using the Air for Pneumatic-Tools, the Air has already been dried enough
as to render any remaining moisture mostly unnoticeable.
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