by Ray H
(wenatchee Wa)

Hello and thanks for taking my question. I have a dewalt D15546 4.5 gallon 1.8hp air compressor. Its only three years old and has had very little use the last two years.

D55146 1.6 HP Continuous, 200 PSI, 4.5 Gallon Compressor

D55146 1.6 HP Continuous, 200 PSI, 4.5 Gallon Compressor

It now takes forever to build to shut off pressure of 212 lbs (45 minutes or more) and sometimes wont even build to that pressure.

After about 150 lbs it just seems to slow way down but just keeps running. I

have done all the troubleshooting tips that you have suggested on this site and everything looks just fine.

I isolated the power source, took the head off and checked the reeds, they looked fine. it has metal fingers on the reeds no corrosion no broken fingers. what else could be the problem? thanks much Ray


D55146 1.6 HP Continuous, 200 PSI, 4.5 Gallon Compressor
by: Bill

The air intake to the pump is clear I expect?

When you checked the compressor valves, was there a gasket, and if so, did you by chance replace it? A weakened gasket can sometimes cause this compressor system.

Next thing I’d check is the line that enters the tank, Ray to be sure that the check valve itself isn’t the problem. Make sure the tank is empty before you break that connection, of course. You want to be sure that the tank check valve itself isn’t impeding air flow into the tank.

After that, if still no relief on your D55146 1.6 HP Continuous, 200 PSI, 4.5 Gallon Compressor, I’d be checking the run capacitor. See the page on this site for how to do that.



Pressure switch
by: Doug in

Couple of points, during or after what Bill said:

That’s supposed to be 200PSI MAX. So, you should look to see if its pressure switch is adjustable, and set it to cut out at 200, not 212PSI.

Second, that high pressure could have contributed to accelerated wear of the piston ring(s), which would slow down the pressure build time.

Let us know….


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