A clogged clothes dryer vent can lead to various problems and symptoms that may affect the performance of your dryer and even pose safety hazards.

Here are some common symptoms of a clogged dryer vent:

1. Longer Drying Times: One of the most noticeable signs is that your clothes take much longer to dry than usual. If it used to take 30-40 minutes to dry a load of laundry, and now it's taking an hour or more, this could be due to a clogged vent.

2. Dryer showing an Error or Fault Code. D80, D90, D95, CF, or AF (these are just a few of the codes). Lint filter light stays on. 

3. Excessive Heat: The dryer may become excessively hot during the drying cycle. Overheating can not only damage your clothes but also pose a fire risk.

4. Clothes Are Hot to the Touch: When you remove clothes from the dryer, they feel hot to the touch maybe still damp, indicating that the dryer is not effectively venting heat and moisture.

5. Musty Smell: A clogged vent can cause moisture to accumulate in the dryer, leading to a musty or moldy odor in both the dryer and your clothes.

6. Excessive Lint Buildup: You may notice an increase in lint collecting in the lint trap and around the dryer drum, little on the lint screen. Lint Blowing around laundry room or collecting in your A/C filter.

7. Reduced Airflow: If you feel little to no airflow from the vent outside while the dryer is running, it's a sign that something is blocking the airflow, possibly a clog.

8. Hot Dryer Exterior: The exterior of the dryer itself may become hot to the touch, which is a safety concern.

9. Increased Energy Bills: A clogged vent can make your dryer work harder and longer, leading to higher energy bills. The dryer could use up to 30% more energy.

10. Dryer Shuts Off Prematurely: Some dryers have safety mechanisms that shut off the dryer if it overheats. If your dryer keeps shutting off before the cycle is complete, it might be due to a clogged vent causing overheating.

11. Burning Smell: In severe cases, a clogged vent can cause the lint inside the dryer to overheat and produce a burning smell. This is a critical safety concern and should be addressed immediately.

12. Dryer Vent Hood Blockage: Check the vent hood (the exterior opening of the vent) outside your home. If you notice debris, lint, or other obstructions around the vent hood, it's a clear sign that the vent is clogged.

It's important to address a clogged dryer vent promptly to ensure the safety and efficiency of your dryer. Regularly cleaning the lint trap and scheduling professional vent cleaning as needed can help prevent these issues. A clogged dryer vent not only reduces the effectiveness of your dryer but also poses a fire hazard, so it's essential to address it promptly.