Compressor Question

It is rated @ 135psi and does cut off @ 135psi, however, within 10 minutes of shut off it looses 5-7psi, and by the next morning it is down to 110psi, where it seems to stabelize. It does not loose any further pressure after this.

I replaced the CHECK VALVE and run it through a 30 minute break in period, but NO help.

Also, I have the shut off valve @ the compressor (OFF),thus eliminating the distribution system.

I have checked the tank and all fittings for leaks, but can't find any.

Any suggestions?
Thanx
Chopper

Yes, my shut off is AFTER the tank, NOT the PUMP.
I'm not the sharpest knife in the drawer but I cut pretty cleanly.

FYI
Since you didn't address my question I assume you don't know the answer either. It may be of interest to you to read the reply from THE PHYSICIST.

Thanks Again for you concern.
Chopper

After your compressor runs you have a 60 gallon tank full of HOT air. AS it cools down the pressure will drop. Your 5-7 PSI drop after 10 minutes is probably normal. I have observed this on a compressor with 80 gallon tank and 160 PSI cutout pressure.

The pressure is proportional to the temperature.

This is an example of Gay-Lussac's Law (See http://www.chem.csus.edu/gaslaws/gay-lus.html ).

Here are some other links to look at. . .

Link

Thanks 1k x 1000 for you’re reply. It makes perfect sense and is so logical. I’m a pretty simple guy (Financial Planner RETIRED), however, I should have been able to deduce the answer for myself. Problem must have been all the brain farts I’ve been having lately.

Prior to my writing YTmag I had contacted De Vilbiss SEVERAL times with this problem, however, no one had a clue (SAD). The best they could do was to send me the new CHECK VALVE I alluded to in my message.

Its reassuring knowing great minds like yours are out there so we don’t have to depend on the corporately trained robots who we call on for answers to questions re: their area of expertise (LOL).

Again, Thanks for you’re greatly appreciated reply…
Chopper

Ironically, my first time in YTMag’s web-site, let alone TOOL TALK Forum.

Yes, I have phoned De Vilbiss and passed your information on to them.

I have no knowledge of any other calls re: the same problem, however, I find it hard to believe others haven’t observed this same condition and called.

I suppose its possible that corporate America has us so subconsciously programmed, that we just accept the fact that (nothing really does what it is advertised to do) and accept this as normal. Who knows?

I could tell you a number of instances that I have perused similar situations with a myriad of products, however, we won’t go there now.

If you would like to communicate from time to time (outside YTMag’s Forum) pass your e-mail address on to me. Mine is box273@hazleton.net

I’m sure we could have some very stimulating communications.

Incidentally;
Did you look at my question re: MAG Welders in the forum?
If so, any opinion on it?

Again, Thanx
Chopper

Read the reply from THE PHYSICIST for the correct answer.

Thans for your reply
Chopper