How to determine if there is an economizer?

[MPdesign]

Hello All,

I know that I have some pretty lame brain questions sometimes so why should this be any different? [:-dunce]

Is it possible to tell visually if a unit has an economizer or not without opening the unit and looking inside at the damper?

I have included a few rooftop package unit examples.

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[Terence McCann]

The short answer is no Joe.

You can have o/a dampers that are just used for 10% makeup/fresh air into the building.

If you are writing a report, and need to verify the presence of an economizer, you really should pull a panel to look and also have a peek at the wiring diagram/control logic.

[MPdesign]

Terry,

Thanks for your help. If I get a large portfolio of work in Ohio, I will definitely try to send some of it your way.

[Marc]

Economizer....just can't remember what that is.

Marc

[MPdesign]

If it is cool outside but warm in the building, it opens the damper further thereby using the outside air as cooling instead of using the compressor.

Also called "Air side Economizer" or "Free Cooling"

The compressor may be turned completely off completely or "partially left on" for dehumidification in some instances and control schemes .

Considering your last post about cleaning calipers in closed systems, I think you are just pulling my leg about forgetting what that is though. [:-thumbu]

Cheers

[Marc]

Ain't pulling your leg. Just forgot what it was.

Here's another one: What do you mean by 'cleaning calipers'.

Marc

[MPdesign]

The forum topic on "Combination systems help". I was just paraphrasing!

Cheers!