Troubleshooting Chart - Speedaire 4MU10A Instrucciones De Operación

Speedaire Operating Instructions
Speedaire
Compressors

Troubleshooting Chart

Symptom
Motor hums and runs
slowly or not at all
E
N
G
Reset mechanism cuts out
repeatedly or fuses blow
L
repeatedly
I
S
H
Excessive noise in
operation
Milky oil in oil reservoir
Excessive oil consumption
or oil in air lines
Water in discharge air
Air blowing out of inlet
Insufficient pressure
Tank does not hold
pressure when compressor
is off and shutoff valve is
closed
Excessive belt wear. (Light
dust from start is normal.
Worn belts separate at
layers)
Tank pressure builds
slowly
Tank pressure builds up
quickly on compressor
ASME safety valve pops
open while compressor is
running
Two-Stage Air
®
Possible Cause(s)
1. Low voltage or no voltage
2. Shorted or open motor winding
3. Defective check valve or unloader valve
4. Defective pressure switch - contacts will not close
1. Pressure switch set too high
2. Faulty check valve, air bleeds
3. Wrong fuse size or magnetic starter heaters
4. Defective motor
1. Loose pulley, flywheel, belt, belt guard, etc
2. Lack of oil in crankcase
3. Compressor floor mounting loose
Water condensing in crankcase due to high
humidity
1. Be sure there is a problem
2. Restricted air intake
3. Wrong oil viscosity
4. Worn piston rings
5. Oil leaks
6. Scored cylinder
Excessive water in tank
Broken first stage inlet valve (two-stage unit)
Broken inlet valve (single stage unit)
1. Air demand too high
2. Leaks or restrictions in hoses or piping
3. Slipping belts
1. Faulty check valve
2. Check all connections and fittings for tightness
3. Check tank for cracks or pin holes
1. Pulley out of alignment
2. Belts too tight or too loose
1. Dirty air filter
2. Blown cylinder head gasket
3. Worn/broken intake/discharge valves
4. Air leaks
Excessive water in tank
1. Wrong pressure switch setting
2. Defective ASME safety valve
Corrective Action
1. Check with voltmeter, check overload relay in magnetic
starter or reset switch on motor. If overload or reset
switch trips repeatedly, find and correct the cause. See
next item
2. Replace motor
3. Replace check valve or unloader valve
4. Repair or replace pressure switch
1. Adjust or replace
2. Clean or replace faulty valve
3. Be sure that fuses and heaters are rated properly
4. Replace motor
1. Tighten
2. Check for damage to bearings, replenish oil
3. Shim and tighten
1. Pipe air intake to less humid air source. Run pump
continuously for one hour
2. Drain oil. Refill with oil of proper viscosity
1. Diagnose oil contamination problems by testing the
discharge air or measuring oil consumption from the
crankcase
2. Clean or replace air filter
3. Drain oil. Refill with oil of proper viscosity
4. Replace rings
5. Tighten bolts, replace gaskets or o-rings
6. Replace cylinder
Drain tank
Replace valve assembly
1. Limit air usage
2. Check for leaks or restriction in hose or piping
3. Tighten belts
1. Clean or replace faulty valve
2. Tighten
3. Replace tank. Never repair a damaged tank
1. Realign motor pulley
2. Adjust tension
1. Clean or replace filter element
2. Install new gasket
3. Install new valve plate assembly
4. Tighten joints
Drain tank, check speed. See Performance table
1. Adjust to lower pressure (175 maximum for two-stage
unit or 135 psi for single stage unit) (See Operation)
2. Replace valve
8
4MU10A, 3VB60
Do not disassemble check valve
with air in tank