Troubleshooting Supply Fan - Greenheck IGX Series Installation, Operation And Maintenance Manual

Problem: Fan does not operate.
Line voltage across L1 & L2, L2 & L3,
and L1 & L3 on main disconnect (DS1)?
Line voltage across T1 & T2, T2 & T3,
and T1 & T3 on main disconnect (DS1)
24 VAC across R and C?
24 VAC across G and C?
24 VAC across A2 and A1 on the RF
relay?
24 VAC across A2 and A1 on the
supply contactor (ST1)?
Line voltage across L1 & L2, L2 & L3,
and L1 & L3 on supply starter (ST1)?
Line voltage across T1 & T2, T2 & T3,
and T1 & T3 on supply starter (ST1)?
Line voltage across T1 & T2, T2 & T3,
and T1 & T3 on supply starter overload
(ST1OL)?
Is motor operating?
Is the fan operating?
Problem: Too much airflow.
Fan speed too high?
Filters in place?
Insufficient external static pressure?
40 Model IGX Make-Up Air
Troubleshooting
Supply Fan
Yes Main incoming power not connected. Connect proper supply
No
power to unit.
Yes
No Main disconnect (DS1) open or defective. Close, repair, or replace.
Main transformer (TR1) circuit breaker tripped. Reset transformer
circuit breaker. If circuit breaker continues to trip, inspect circuit for
improper wiring or grounding.
Yes
Main transformer (TR1) failed. Replace main transformer.
No
Phase monitor (PM) contact open. Correct incoming phase order at
disconnect.
Fuse (FU6) blown. Test and replace blown fuse(s).
Fan switch (S2) open or not wired. Close or wire fan switch.
Yes Fire system contact (FSC) tripped/not installed. Correct or replace.
No
If fan switch and fire system contact is not required, place jumper
from R to G to make the fan run continuously.
Freeze protection tripped. Cycle disconnect to reset.
Supply fan overload tripped. Push reset button on overload or VFD
to reset. Check motor amp draw and correct as necessary.
Yes Damper limit switch (D1L) not closed.
No
Damper stuck closed or actuator failed. Repair damper
interference or replace actuator.
Exhaust fan contactor not powered. Close or wire exhaust switch,
reset exhaust overload, or replace faulty exhaust contactor.
Yes RF relay failure. Check for loose connection or bent relay pins, repair
No
or replace relay.
Yes
No Supply motor fuse (FU1) blown. Test and replace blown fuse(s).
Yes
Supply starter contact (ST1) not closed. Replace contactor.
No
Yes
Supply overload (ST1OL) faulty. Replace overload.
No
Motor wired incorrectly. Check and correct motor wiring.
Yes
No
Defective motor/capacitor. Repair or replace.
Yes Broken fan belt. Replace. Reference Maintenance, General, V-Belt
No
Drives.
Everything is working properly, consult factory.
No
Adjust drives or VFD as needed. Reference Supply Fan, Start-Up.
Yes
Yes
No Install filters.
Yes Increase external static pressure.
Everything is working properly, consult factory.
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