Troubleshooting

Trouble	Cause	Remedy

	System congestion.	Clean the entire system.

Obstacles to the air flow.

Low air flow

Check the real obstacles area and the inlet shape towards the original design.

In dry-coolers the minimum free height of the inlet area has to be 1 time the fan diameter at least; this height has to be higher in case of multiple units in line.

Low power absorption	Static pressure higher than the specified	Increase blade pitch angle (till 3º after checking the data
Low power absorption	one.	sheet selection.
	one.	sheet selection.

	Pitch angle lowered by blade rotation	Set the right pitch angle and refer to the operation manual
	(e.g. screw (15) not tightened at the right	to set the right torque of screws and bolts.
	torque).
	Temperature higher than the design.	Increase blade pitch angle (till 3º after checking the data
	Temperature higher than the design.	sheet selection.
		sheet selection.

	Temperature lower than the design.	Decrease blade pitch angle (till 3º after checking the data
	Temperature lower than the design.	sheet selection.
High power absorption		sheet selection.

	Static pressure lower than the design.	Decrease blade pitch angle (till 3º after checking the data
		Decrease blade pitch angle (till 3º after checking the data
		sheet selection.
		sheet selection.

	Screws and bolts of the fan and/or the	Torque all screws and bolts.
Rubbing between the	structure loosened.
blades and the fan ring	Fan not centered.	Center the fan.
	Tip clearance too small.	Increase the fan ring diameter.

	Unbalance of one or more blades.	Contact SPX Cooling.

	Blade pitch angle not included in the 0.5º	Set right blade pitch angle.
	tolerance.
	Blades too close to supports (periodic aero-	Contact SPX Cooling.
	dynamic turbulence).
	Resonance between one of the possible
	forcing frequencies of the fan and one or	Contact SPX Cooling.
	more of the vibration modes of the structure	Contact SPX Cooling.
	on which it is installed.

High vibration level	Vibration transmitted by the structure on	Contact SPX Cooling.
	which the fan is installed.	Contact SPX Cooling.
	which the fan is installed.

	Resonance of the blades with one of the	Contact SPX Cooling.
	possible forcing frequencies.
	Misalignment of the drive shaft.	Realign of the drive shaft.

	Worn output shaft bearing.	Contact the supplier.

	The fan and/or the structure bolts are not	Tighten screws and bolts at the right torque.
	tightened.
	The draining holes of the blades are ob-	Open the draining holes.
	structed.