capacity control for 100% fresh air dx system

[coztemur]

hi

I would like to assemble a DX system with 100% fresh air.
I know that I have to use some capacity control system.
If I want to use hot gas bypass, which electronic controller I should use,
and what will be my controlling parameter? (limiting suction pressure, setting leaving air temperature from the coil ...??) and how??

Best regards

Coskun

[NoNickName]

Suction pressure is the way to go.
As for the application, I would install a self regulated hot gas bypass, without any electronics. Sporland, Danfoss and other have it in the their catalogue.
I would prefer chilled water, anyway.

[coztemur]

Self regulating hot gas bypass is ok but
I want high precision controll of set point as well
If I chose electronic controlle one what shall I do??

[NoNickName]

If you want high precision, you need a very fast modulating bypass valve and will cost an arm and a leg. Been there, done that, doesn't satisfy. Electronic control is not a guarantee of good control.
I would go with chilled water coil.

[absrbrtek]

Try here: http://www.rawal.com/ these will give you precision control.

[coztemur]

I checked the site, it looks like ordinary hot gas bypass valve. what is the benefit or difference?