Air leaks can be a significant source of wasted energy on Quincy air compressors. They will cause pressure drops in the system, as well as resulting in additional costs. This article will provide why your Quincy air compressor leaks air, and the most likely locations if you’re looking to diagnose and fix the issue!
Table of Contents
- Why Is Air Leaking From My Quincy Air Compressor?
- Useful Pages on Air Compressor Leaks
- FAQs (Frequently Asked Questions)
- Reader Questions & Responses
Why Is Air Leaking From My Quincy Air Compressor?
Quincy air compressors leak air for a number of reasons. It could be that the fittings are not sealed, the hose or pipe has a crack, or a compromised component that needs replacing. Here’s a list of the most common components that may be causing your Quincy air compressor to leak:
- Condensate traps
- Couplings
- Cylinder rod packing
- Disconnects
- Filters
- Fittings
- Flanges
- Hoses
- Lubricators
- Point-of-use devices
- Pipe joints
- Pressure regulators
- Shut-off valves
- Thread sealants
To help you locate your Quincy air leak, you typically have 3 methods to choose from:
- Listening and feeling – is the simplest method, but not always the most accurate.
- Applying soapy water to an area where a leak is suspected – is a reliable but time-consuming method.
- Using an ultrasonic leak detector – is the best method and has quickly become an industry standard.
For more information on how to find and fix leaks on your air compressor, visit our guide!
Useful Pages on Air Compressor Leaks
- Compressed Air Leaks – How to Find And Fix Leaks In compressed Air System
- Air Compressor Quick Connect Leaks – Why & How to Fix
- Air Compressor Leaking Air – How to Fix Air Compressor Leak
- How To Fix An Air Compressor Tank Leak
- How To Fix A Leaky Air Compressor Hose – Stop Air Compressor Hose Leaking
- PRVs keep leaking – Air Compressor Pressure Relief Valve Leaking
FAQs (Frequently Asked Questions)
Your Quincy air compressor is leaking air because you may have fittings that are loose and not sealed properly, the air hose or pipe has a hole, or a component is compromised and needs repairing or replacing.
Reader Questions & Responses
Quincy Air Compressor Unloader Valve Leaking – Quincy Air Compressor Troubleshooting
Question
We have a Quincy QR 310 air compressor with our liquid nitrogen plant. Quincy Air compressor unit is supposed to maintain 90 – 130 PSI pressure in the air tank. So when pressure is 130 PSI, the compressor motor stops and when pressure is 90 PSI motor automatically starts. It was working fine for the last three years.

But now as soon as the compressor motor stops (after achieving a pressure of 130 PSI), air flows out from the top (from the unloader tower) see the attached photo.
I checked for a diaphragm in the unloader assembly, it looks fine no cracks. What can be wrong? It leaks air when the motor is off, no leak when the motor is running.
Response
The Quincy 310 is the pump. Assuming you have this pump attached to a tank, here’s a good place to start, Ram.
https://www.about-air-compressors.com/pressureswitch/
Though this page refers to a pressure switch leaking, the cause of that, and the likely reason for your Quincy unloader leaking are, I think, the same. I’m pretty sure it’s a check valve.
Have a look at the page, and add a comment if there’s still a problem.
If you have any questions regarding a Quincy air compressor leaking air, please leave a comment below, with a photo if applicable, so that someone can help you!