Why is the dew point warning showing on my Quincy QGD compressor?
Short answer: High dew point warning (integrated dryer). If your Quincy QGD 40-60 / QGS 40-100 (Airlogic2 controller) is showing Dew point temperature warning, the controller has logged a specific, documented condition. This page covers what it means, what causes it, what you can safely fix yourself, and when — and why — it takes a technician.
What exactly is the machine telling you?
On compressors with the integrated dryer, a warning appears if the pressure dew point is too high — the air is leaving wetter than specification. Documented causes include high inlet or ambient temperature, a clogged condenser, or refrigerant problems.
Which machines show this?
Quincy QGD 40-60 hp and QGS 40-100 hp rotary screw compressors with the Airlogic2 display controller, including Full Feature packages with the integrated refrigerated dryer. Like Quincy's smaller INFOLOGIC machines, these display icons and text messages, not numbered fault codes — a lit alarm LED means a warning, a flashing one a shutdown, and the specific condition is spelled out on the controller's screens and logged in the Event History menu. Warning and shutdown levels for temperatures are programmed values with factory settings, so your machine's exact trip points can differ. Two habits the manual insists on: the emergency stop does not make the machine voltage-free, and service timer changes go through the authorized distributor.
What causes it?
- High inlet or ambient temperature loading the integrated dryer
- Clogged dryer condenser (or aftercooler)
- Condensate drain not discharging — test it with the drain's test button
- Refrigerant shortage or circuit problems when the basics don't fix it
Can you fix it yourself?
Often — cool or duct the intake air, clean the condenser with power off, and prove the drain works. A dew point that stays high after that is a refrigeration-circuit problem.
Step by step — what to try, in order:
- Check and reduce the ambient/room temperature if possible; duct cooling air from a cooler place
- With power off, clean the dryer condenser and, if needed, the compressor aftercooler
- Verify the condensate drain works (use the drain's test button on electronic drains)
- Restart and watch the dew point reading
When do you need a technician — and why?
Refrigerant charge and circuit checks on the integrated dryer must be done by a refrigeration-qualified technician — handling refrigerant is licensed work.
If it does come to a service call and you're in Nashville, TN or Birmingham, AL, we maintain independently compiled lists of local companies that service industrial air compressors — real businesses with verified contact information, none of whom paid to be listed.
Related questions
What does Dew point temperature warning mean on a Quincy QGD 40-60 / QGS 40-100 (Airlogic2 controller)?
High dew point warning (integrated dryer). On compressors with the integrated dryer, a warning appears if the pressure dew point is too high — the air is leaving wetter than specification. Documented causes include high inlet or ambient temperature, a clogged condenser, or refrigerant problems.
Can I fix Dew point temperature warning on a Quincy QGD 40-60 / QGS 40-100 (Airlogic2 controller) myself?
Often — cool or duct the intake air, clean the condenser with power off, and prove the drain works. A dew point that stays high after that is a refrigeration-circuit problem.
When does Dew point temperature warning on a Quincy QGD 40-60 / QGS 40-100 (Airlogic2 controller) need a technician?
Refrigerant charge and circuit checks on the integrated dryer must be done by a refrigeration-qualified technician — handling refrigerant is licensed work. Call a refrigeration-qualified technician if the dew point stays high — refrigerant shortage and circuit checks must be done professionally.
Verified against service documentation: Quincy QGD 40-60 / QGS 40-100 (Airlogic2 controller) documentation for Dew point temperature warning (compressorworld.com)