Munters CURTAIN 1 FAIL

What does Munters CURTAIN 1 FAIL mean?

On a Munters Smart C/D climate controller, CURTAIN 1 FAIL means curtain 1 is not moving properly. The manual lists this as an alarm shown when the controller cannot drive or position the curtain as commanded. Because curtains regulate ventilation, a stuck or unresponsive curtain can compromise the building's climate control.

Symptoms

• CURTAIN 1 FAIL alarm shown on the main screen
• Curtain 1 does not move to its commanded position
• Alarm relay activates and the message repeats until the fault is cleared
• Ventilation through curtain 1 is reduced or uncontrolled

Common causes

• Cable to the curtain is disconnected
• Curtain potentiometer is faulty
• Curtain's motor is not working properly

Diagnostic steps

1. 01

   Acknowledge the alarm

   Press OK on the main menu to reset the alarm relay; the manual notes the message continues until the problem is resolved.

2. 02

   Check the curtain cable

   Inspect for a disconnected cable to curtain 1, a cause listed in the manual.

3. 03

   Check the curtain potentiometer

   Verify the curtain potentiometer is working, since a faulty potentiometer is given as a cause; the manual covers potentiometer calibration in the Calibration menu.

4. 04

   Check the curtain motor

   Confirm the curtain's motor is operating, as a motor not working properly is listed as a cause.

When to call a professional

The Smart C/D manual cautions not to open the controller box if a hardware problem arises and to contact an authorized electrician. Call a qualified technician if the curtain still will not move after checking the cable, or if diagnosing the potentiometer or replacing the curtain motor is beyond your experience, since this involves powered drive components and controller wiring.