Dewalt D55151 Type 3 reduce pressure switch settings

by John Hazelrigs
(Smyrna, GA USA)

When my Dewalt D55151 Type 3 continued running, I replaced the pressure switch. I failed to realize the replacement switch (Lefoo LF10-1) came with cut in and out pressure 140/175 psi. I need to reduce it to the factory settings for my compressor of 85/115 psi.

I removed and cleaned the check valve and unloader. It appears to be functioning. However, due to my lack of knowledge I can not be certain there is not an issue with it.

When the compressor is running, it appears that air is escaping thru the unloader tip. Is this normal?

Also, the compressor will run until the safety valve dumps air and continues to run before and after releasing air.

Your advice regarding my compressor issues is greatly appreciated. Your website is very helpful - especially for guys like me lacking training and experience diagnosing and repairing compressors. Thank you.


Comments for Dewalt D55151 Type 3 reduce pressure switch settings

Click here to add your own comments

Apr 12, 2017
pressure settings
by: Doug in

Did you look under the hood?

Seems you got the wrong switch, as most of the Lefoo LF10-1's are 85-125.

Anyway, there are (usually) a couple screw adjustments that *may* allow you to set it as desired. That's the first thing - the rest is likely incidental to those pressure settings.

If what you have is not adjustable, you'll just have to spring for the correct one.

Good luck.

Click here to add your own comments

Add your own question or comment. It's easy to do. How? Simply click here to return to DeWalt Air Compressor Issues.