Van Air Systems Sentinel MDV-400L Series User Manual
Page 4

PAGE 4
2950 Mechanic Street
Lake City, Pa 16423 USA
Phone: 800-840-9906
Fax: 814-774-0778
www.vanairsystems.com
Note: Service work to be done by qualifi ed personnel only! Always remove pressure and power from the unit before servicing.
TROUBLE SHOOTING
PROBLEM
CAUSES
SOLUTION
Unit will not operate (No
display on LCD)
No power
Check power supply. Check circuit breakers or fuses. Check to see if circuit has a
remote power on/off switch.
Fuse F1 is blown
Replace Fuse F1.
Unit will not operate (“VALVE
FAULT” displayed on LCD)
The control board did
not sense that the
next position, closed
or open, was reached
for a period of 15
seconds
Turn power off and back on. Press and hold Mode and Enter buttons simultaneously
for 3 seconds. If “OVERRIDE” is displayed but valve does not rotate, fuse labeled F2
on bottom board is blown. Replace fuse. If “OVERRIDE” is displayed, valve rotates
continuously and valve fault reappears, then optic sensor has failed. Contact factory.
If “OVERRIDE” is displayed, valve rotates and the timer closed time appears, then the
“VALVE FAULT” has been cleared.
Unit will not operate (LCD
display working properly)
Faulty actuator/motor/
valve assembly
Press and hold the Enter and Mode keys simultaneously for 3 seconds. If the actuator
motor turns but the valve does not, check for a broken or loose valve stem. If the stem is
broken, replace the valve. If this is not the problem, replace the entire unit. If the motor
will not turn after power is applied directly to it, the motor has failed and the unit must be
replaced.
Valve binds during rotation
Ball valve seats worn
Replace the ball valve.
Ball valve ball clogged
or damaged
Free valve of any debris. If valve is damaged, replace.
Ball valve leaks prematurely
Defective ball valve
Replace ball valve.
Valve set on short
cycle time
Ball valve should be replaced at some time between 100,000 and 150,000 cycles (will
vary with application). If cycle times are set below 5 minutes, then the ball valve will
most likely require replacing within the warranty period (based on 24-hour per day
operation). This is considered normal wear and not covered under warranty.
Display reads “OPEN” or
“CLOSED” and valve is in
the opposite position
Power Interruption
Press and hold the Enter and Mode keys simultaneously for 3 seconds. Valve will
rotate to the closed position.
VAN AIR PARTS AND SERVICE
PHONE: 888-606-9303
FAX: 814-774-0778
E-MAIL: [email protected]