fan speed control

[the rock]

hi

i have a chiller that has two condenser fans
one fan is controlled by a fan speed controller and the other by a pressure switch
what would be the correct way to set up the fans say to a pressure of 17 bar

the rock

[monkey spanners]

How was it set up originally?

[Brian_UK]

I may be reading this wrong but if you want 17 bar then set the controls to give 17 bar.

[nike123]

Both should be on fan speed controller.

[Reeferman27]

One fan should be speed controlled to allow discharge to build to the required setting and the second should start if the pressure reaches the pressure switch set point.

eg 0-17barg = 1st fan (speed controlled) at variable speed, 2nd fan off (night time or low amb.temp)
over 17.1barg = 1st fan (speed controlled) at full speed, 2nd fan on (Day time or high amb. temps.)

Although both fans could be speed controlled and the pressure switch is a cut out on HP?????

[the rock]

hi Reeferman27

thank you for your input thats how i thought it would be set up but not having seen one fan controlled by a fan speed controller and one by a pressure switch before i thought i would check

thanks for all of the replies

the rock