DeWalt D55170 Instruction Manual page 21

Code Possible Cause
20 Defective motor, motor capacitor or pressure switch.
21 Air compressor is not large enough for air required
22 Possible defective safety/relief valve
23 Excessive air tank pressure
24 Defective gaskets
25 Fittings not tight enough
26 Defective or rusted air tank
27 Pressure regulator knob not turned to high enough pressure
28 Hose or hose connections are to small or long.
29 Possible defective (reed) valve.
30 Air compressor on unlevel surface.
31 Crankcase overfilled with oil.
32 Plugged oil crankcase vent.
33 Water in oil due to condensation.
34 Condensation in air tank caused by high level of atmospheric
humidity.
35 Unit located in damp or humid location.
36 Tanks have air pressure
Possible Solution
Contact D WALT Customer Service at 1-800-4DEWALT.
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Check the accessory air requirement. If it is higher than the CFM
or pressure supply of the air compressor, you need a larger air
compressor.
Operate safety relief valve manually by pulling on test ring. If it
still leaks, replace.
Adjust pilot valve. If problem still exists replace pilot valve.
Replace and torque head bolts to 6 - 7 ft lb
Warning drain air before tightening: tighten fittings where air can
not be heard escaping. Check joint with soap solution. Do not
overtighten.
Air tank must be replaced. Do not attempt to repair air tank.
Adjust pressure regulator knob to proper setting or replace.
or defective pressure regulator.
Replace with larger hose or connectors.
Remove pump head and inspect valve plate and (reed) valve.
Clear or replace valves as required.
Do not incline the air compressor more than 10˚ in any direction
while running.
Drain oil. Refill to proper level with D
Clean.
Drain oil. Refill to proper level with D
Drain air tank after every use. Drain air tank more often in humid
weather and use an air line filter.
Relocate unit.
Bleed tanks fully.
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WALT synthetic oil.
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WALT synthetic oil.
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