I have a Husky air compressor, about 1 year old, 30 gallon vertical tank, with the separate motor & pump. Problem is the tank will leak out all it's air overnight, compressor is in my shed and I live in Florida. I let the compressor fill to it's shutoff pressure and sprayed all the fittings and welds with soapy water but do not see anywhere that is leaking. To eliminate the fittings being a source of the leak I took the pressure switch out of the tank and installed a air gauge in it's place, I than filled the compressor to 125PSI and unplugged the motor. First couple of minutes pressure dropped about 5 PSI. After approx 2 hours pressure has dropped to 114, (will update pressure in a few hours), I sprayed all the fittings, welds and pump with soapy water again and still do not see any signs of a leak. Any ideas where else to check? Line going from pump to tank has not been touched and should have the check valve installed as it is the same way it was when I bought it. Another thing was looking up info on compressors and on the CHpower site they show a breather where the oil fill is, mine did not come with a breather just a screw in plug, how important is it to have that breather installed? Compressor works fine other than the leak.

this is the compressor I have:

http://www.homedepot.com/webapp/wcs/...egoryID=524403

 

I have that exact same compressor. Got it about 3 weeks ago. No leaks that I can detect, does not lose any air pressure. The breather was supplied seperate, I had to remove the oil filler cap and replace it witht the breather. Have you looked at the drain plug on the bottom yet? I replaced mine with a 90 degree elbow, a 6" nib and a valve cuz the drain valve was such a PITA to get to.

 

One thing you can't check is back bleed through the compressor piston rings. I have a 26 gallon CH and I have given up on it. It will leak down over a period of a few days.....sometimes. Other times it will stay charged just fine. It'll drive you batty.

 

There is a check valve, normally at the tank where the discharge line from the compressor connects.
Pump up the tank and when the compressor shuts off unplug it.
Next remove the discharge line at the compressor head and check for air leaking by the check valve.

Valves or rings in the compressor will not be responsible for pressure loss.
Bad valves and/or rings will cause a loss of capacity.

 

I just went out and checked the pressure and it is holding (so far) at about 114 PSI, I'll wait until tomorrow and check it again, if there is a large drop I will pull the copper line from the pump and check it for a leak coming thru the check valve. I know that just because there is a check valve doesn't mean it can't leak back, I have a check valve on the output of a air compressor I have in my car for my air horn and one day it got stuck slightly ope, I had to take it apart and clean it than it was ok again. Right now I can't re-install the pressure switch as earlier I was tightening a fitting and cracked the aluminum so I need to get a new pressure switch, actually I needed a new one anyway as the plastic on/off knob broke on it.

I agree the drain valve design is a bad one, almost impossible to get at the way they designed it, I'll have to do as you did as soon as I figure out where this tank is losing air from.

I don't think air loss like I have can be considered normal, at my job they just bought a 80 gallon vertical compressor from Lowes and every night before we leave they shut the power off going to it and I've noticed the next day the pressure is always high.

 

just went out and checked the pressure, it is still up there pretty good, it's dropped a few PSI but I think that would be considered normal. It's right around 111 PSI now. So I guess this all means that something in the pressure switch or other parts that attach to the pressure switch was causing the small leak. As I said I removed the whole pressure switch assembly and put a gauge in it's place just to monitor the pressure in the tank.

almost forgot, I pulled the copper line from the compressor pump and no air leaking so the check valve is working.

So time to get a new pressure switch, I would really like to find/get another brand, the one that came with the compressor is mostly plastic and cheap looking inside, I would like to find one that may last more than a year, possibly one from Square D or similar, the other requirement being I don't want to have to pay $80 or more for one.

thanks for the help

 

pressure is still holding at 111 PSI, a nice change from how the tank usually loses all it's pressure overnight. Hopefully when I get a new pressure switch it will still not leak.

 

Just for the record, Greg, if the check valve is faulty, air will pass back through the compressor head, valves and rings.

 

I think that is what I was saying.
It is correct the check valve keeps the air in the receiver tank so it doesn't leak back through the reed valves in the compressor.

You had referred to not being able to check back bleed through compressor piston rings but we were talking about pressure loss from the tank which is not related.

 

pressure still holding at 111 PSI, this is so much better than it usually is!! At least I now know the tank isn't leaking. Now I just have to get a new pressure switch.

 

To answer your question about a breather - get one. They probably put a plug in instead because oil will spill out if you tilt the unit too much while moving it. But you need it. Otherwise, you get condensation in the crankcase, oil will mix with water and that's not good.

 

thanks, don't know if I can get just the breather, I was looking at the parts list/picture and the breather looks like it is included with the pump. Maybe a generic breather will work ??

 

The phone number for technical assistance and replacement parts is 1-800-543-6400.

The breather is part number VH901100AV.

This is taken from the instruction manual I received with my VT6315 about 3 weeks ago.

 

thanks for the number, I was looking on the CHproducts site and didn't see that part listed on any of the parts lists.

 

Glad to help. Hope you can get the right part.