Bosch WTG90 Dryer Leaking Moisture from Vent

Introduction

Dryers are a staple of modern households, turning wet laundry into crisp, ready‑to‑wear garments in a matter of minutes. Yet, even the most reliable machines can develop quirks over time. One common complaint from Bosch WTG90 owners is that moisture seems to leak from the vent system, leaving damp clothes or a dampened floor in the laundry room.

This article breaks down why this problem occurs, how to spot it, and step‑by‑step solutions to get your dryer running dry again. Whether you are a DIY homeowner or simply want to understand the mechanics behind the issue, this guide will equip you with the knowledge to troubleshoot and resolve vent‑leakage problems in the Bosch WTG90 dryer.

Common Causes of Moisture Leaking from the Vent

When a dryer’s vent appears wet or damp, a few typical culprits are usually at play. Knowing these can save you time and effort when you start the diagnostic process.

1. Blocked or Cracked Vent Hoses

A vent hose that has become cracked, kinked, or partially blocked can allow steam and moisture to escape into the surrounding air. The Bosch WTG90 uses a flexible metal or plastic vent that connects the dryer to the outside venting system. Over time, dust, lint, or even pets can squeeze into cracks, causing the hose to buckle.

2. Improper Vent Placement or Poor Seal

The vent opening on the wall or door may not be sealed correctly. If the vent cap has gaps or if the door seal is damaged, steam can leak out before it exits through the duct. This is common in older homes where the vent opening was not designed to accommodate modern dryer vents.

3. Clogged Lint Trap or Ductwork

Even if the hose itself is intact, lint buildup in the lint trap, duct, or vent cap can restrict airflow. Reduced airflow forces more moisture into the dryer chamber, which may be forced out through any small gaps or cracks.

4. Faulty Dryer Door Seal

The door seal on the Bosch WTG90 is designed to keep hot, moist air inside. A compromised seal can allow steam to escape through the door, making the vent look damp.

Diagnostic Checklist

Before you begin any repair work, it is essential to confirm that the moisture is indeed originating from the vent system and not from other sources (e.g., a leaking water pipe). Follow this checklist:

1. Check for Water Damage on Surfaces
   Inspect the floor, walls, and any adjacent surfaces for dampness or water stains that could indicate a hidden leak.

2. Observe the Dryer’s Interior Temperature
   Run the dryer for a short cycle and monitor the internal temperature. A significantly higher temperature may suggest a vent obstruction.

3. Feel for Steam at the Vent
   With the dryer running, gently feel around the vent opening and hose. A warm, moist feel often points to leakage.

4. Inspect the Lint Trap
   Remove the lint trap and inspect for lint accumulation. A full lint trap can cause the dryer to work harder, generating excess moisture.

5. Visual Inspection of the Vent Cap
   Look for cracks or gaps in the vent cap and examine the outside venting area for lint buildup.

If any of these checks reveal a problem, proceed to the repair section. Otherwise, the issue may stem from an internal component that requires professional attention.

Step‑by‑Step Fixes for Vent‑Related Moisture Leaks

1. Clean and Inspect the Lint Trap and Vent Hose

1. Unplug the Dryer – Safety first.
2. Remove the Lint Trap – Pull it out and check for lint accumulation.
3. Flush the Hose – If the hose is accessible, rinse it with warm water to remove lint.
4. Check for Cracks – Inspect the entire length of the hose for visible cracks or splits.
5. Replace if Necessary – If any damage is found, replace the hose with a new, Bosch‑approved part.

2. Tighten or Replace the Vent Cap

1. Access the Vent Cap – If the cap is inside the room, remove any screws or clamps holding it in place.
2. Check the Seal – Look for gaps where steam could escape.
3. Replace Seals or the Cap – If the cap is old or damaged, purchase a new vent cap that matches the size and shape of your existing one.
4. Re‑install – Secure the new cap and test the dryer for leakage.

3. Sealing the Vent Opening

1. Inspect the Door Seal – Look for wear, tears, or missing seals around the dryer door.
2. Replace the Seal – Purchase a Bosch‑approved door seal kit.
3. Apply Properly – Follow the manufacturer’s instructions for installation.
4. Test – Run a short cycle and observe for any remaining moisture.

4. Verify External Vent Pathway

1. Open the Vent to the Outside – Remove the vent cover on the exterior wall.
2. Check for Lint – Remove any lint or debris.
3. Inspect for Kinks – Make sure the duct runs straight and is not compressed by furniture or pipes.
4. Add a Vent Cap – If not already present, install a vent cap to protect against rain and debris.

Maintenance Tips to Keep Your Vent Dry

Prevention is always cheaper than repair. Follow these simple habits to keep your dryer’s vent system dry and efficient.

• Clean the Lint Trap After Every Use – A full trap slows airflow and increases moisture.
• Inspect the Vent Hose Once a Month – Look for cracks or signs of wear.
• Schedule an Annual Professional Cleaning – A technician can clean the entire duct system and check for hidden problems.
• Avoid Overloading the Dryer – Too many clothes in a single cycle can cause excessive moisture.
• Use a Dryer Vent Cleaner – Specialized cleaning brushes help remove lint from hard‑to‑reach areas.

When to Call a Professional

Despite the ease of many fixes, some problems require specialized tools or expertise.

• Persistent Moisture After Repairs – If moisture continues to leak even after replacing hoses and seals, a deeper inspection is needed.
• Suspected Electrical Issues – If the dryer starts producing excess heat or appears to be malfunctioning electrically, call a licensed electrician.
• Complex Vent Ductwork – Homes with multi‑room venting or long duct runs may need a professional assessment to ensure all connections are secure.

Frequently Asked Questions

Why does my Bosch WTG90 dryer produce moisture on the vent after a few cycles?

A blocked or partially blocked vent can trap moisture inside the dryer, forcing it out through any weak spots.

Can I use a standard vent hose with my Bosch dryer?

Only use hoses approved by Bosch. Incorrect sizes or materials can create leaks or reduce airflow efficiency.

Is it safe to use a dryer vent cleaner while the dryer is running?

No. Always unplug the dryer before cleaning the vent system to avoid accidents.

How often should I replace the dryer’s door seal?

Typically every 2–3 years or when you notice gaps, cracks, or a lack of heat retention.

Conclusion

Moisture leaking from the vent of a Bosch WTG90 dryer is usually a symptom of a blocked, cracked, or improperly sealed vent system. By following a systematic diagnostic approach, cleaning and replacing critical components, and maintaining regular cleaning habits, you can restore your dryer’s performance and protect your living space from dampness.

If the issue persists or if you encounter electrical concerns, do not hesitate to reach out to a qualified service technician. With attentive care, your dryer will continue to be a reliable ally in your laundry routine.