How to Fix Flow Sense / d80 d90 d95 alert on LG DLGX7701VE (Gas)

Flow Sense / d80 d90 d95 alert

In this step-by-step repair guide, I’m here to help you fix the flow sense / d80 d90 d95 alert on your LG DLGX7701VE (Gas). With the right tools and parts, most homeowners can complete this repair in about 1–2 hours and avoid a costly service call.

Part of our Top 20 Dryer Models & Common Repair Issues Guide. Browse all dryer repair guides for related models and issues.

Common Symptoms & Causes

If your LG DLGX7701VE is displaying a Flow Sense warning, here are the most common signs you’ll notice during operation.

• The dryer display shows a d80, d90, or d95 alert code during or after a cycle
• Clothes feel damp or take multiple cycles to fully dry
• The drum becomes excessively hot to the touch while running
• The dryer shuts off early before the cycle completes

These issues are most commonly caused by a clogged or kinked exhaust vent duct, built-up lint restricting airflow, or a crushed vent hose behind the dryer.

Safety First

• Unplug the dryer from the power outlet before starting any repair — never work on a live appliance.
• Wear work gloves when handling metal brackets, sheet metal edges, or sharp components.
• Take photos with your phone before disconnecting any wiring harnesses or connectors.
• Work in a well-lit area with enough floor space to lay removed panels flat.

Tools & Parts Needed

Essential Tools

• Phillips #2 screwdriver
• ¼” nut driver
• Putty knife
• Multimeter
• Work gloves

Replacement Parts

• Flexible vent brush kit (12 ft)
• 383EEL9001L Side Vent Kit Universal for LG Dryer
• metal hose clamps
• duct tape (foil)

Step-by-Step Repair Instructions

Step 1

The d80, d90, and d95 codes are LG Flow Sense alerts indicating the exhaust duct is 80%, 90%, or 95% restricted — a condition that forces the dryer to work harder, extends drying times, and creates a serious fire hazard from lint buildup and heat. I advise against continuing to operate the dryer until the vent is cleaned, as restricted airflow can cause overheating and ignition of accumulated lint. Addressing this immediately protects both the appliance and your home.

Step 2

Unplug the dryer before doing any work, then disconnect the vent hose at the back of the unit by loosening the metal hose clamp with a 5/16” nut driver — this gives you direct access to the duct interior where lint compacts over time and blocks airflow. I recommend feeding a flexible rotating brush into the duct and working it through the full length of the run, because lint accumulates throughout the duct, not just near the dryer. Pro tip: a drill-powered brush kit moves through bends more effectively than a manual rod and dislodges compacted lint that hand tools often miss.

Step 3

Clean from both ends by removing the exterior vent cap screws (typically two Phillips-head screws) and inserting the brush from outside inward, since lint near the exterior cap is often the densest and most restrictive section of the run. Pulling lint accumulation from the outside prevents debris from being pushed deeper into the duct rather than removed. After cleaning, check that the exterior damper flap opens freely, as a stuck or lint-blocked damper can trigger Flow Sense alerts.

Step 4

Inspect the entire duct run and replace any accordion-style plastic or foil flex duct with rigid 4-inch metal duct. The ridged interior of flexible duct catches lint at every corrugation and builds restriction far faster than smooth-wall metal pipe. Plastic flex duct is also a fire code violation in many jurisdictions and can collapse or kink, worsening the airflow problem. If you need a short flexible section to connect the dryer to the wall, use only UL-listed semi-rigid aluminum flex, keeping it as short and straight as possible.

Step 5

Calculate your total equivalent duct length to confirm the installation is within spec: each 90-degree elbow counts as 5 feet of equivalent run, and the total equivalent length for most gas dryers — including this LG model — must not exceed 25 feet. Exceeding this limit means the blower motor cannot maintain adequate airflow even through a clean duct, which will cause Flow Sense codes to return. If your run genuinely exceeds 25 feet equivalent, I suggest installing an inline duct booster fan rated for dryer exhaust to restore sufficient airflow.

Step 6

Reassemble all duct sections using metal hose clamps at each joint and seal every seam with foil-backed metallic tape — never use standard duct tape, which degrades rapidly under the heat and humidity of dryer exhaust and allows lint-laden air to leak into wall cavities. Once everything is back together, plug the dryer back in and run a full cycle; the Flow Sense alert will clear automatically once the control module detects restored airflow throughout the cycle. If the alert persists after one full cycle with a confirmed clean duct, inspect the internal exhaust path inside the dryer cabinet, as a lint blockage at the blower wheel or internal ducting can produce the same codes.

Where to Buy Replacement Parts

You can find genuine OEM and aftermarket replacement parts for your LG DLGX7701VE (Gas) on Amazon:

• dryer vent cleaning brush kit 12 foot flexible rotating
• 383EEL9001L Side Vent Kit Universal for LG Dryer
• rigid metal dryer duct 4 inch diameter replacement

When to Call a Professional

If the issue persists after completing all steps above, the problem may involve a failed main control board, a defective heating element or thermal cutoff, or wiring that requires specialized diagnostic equipment. In such cases, I recommend contacting a licensed appliance technician. And remember, for gas dryers, do not attempt work on the gas valve or supply line — that work is restricted to a licensed gas fitter in most jurisdictions.

How Much Does This Repair Cost?

DIY parts for fixing a Flow Sense alert — such as a replacement vent hose or exhaust duct — typically run $10–$50. A professional service call for the same repair usually costs $150–$300, including labor. Tackling this yourself can save you over $100 while restoring your dryer’s performance quickly.

Frequently Asked Questions

What does the d80, d90, or d95 alert mean on my LG DLGX7701VE?

These Flow Sense codes indicate your dryer’s exhaust airflow is restricted, with d95 being the most severe blockage. A clogged lint trap, kinked vent hose, or blocked exterior vent cap are the most common causes.

Is it safe to keep running my gas dryer while the Flow Sense alert is active?

No, you should stop using the dryer until the issue is resolved. Restricted airflow on a gas dryer can lead to overheating and creates a potential fire hazard.

How often should I clean the dryer vent to prevent Flow Sense alerts?

Clean the entire exhaust vent system at least once a year, or more frequently if you run multiple loads daily. Regular maintenance can significantly reduce the chance of blockages triggering these alerts.

Recommended Products

These are the parts and tools I recommend for this repair, based on compatibility and customer reviews:

• Sealegend 58-Pieces 35-Feet Dryer Vent Cleaner Kit, Dryer Cleaning Tools, Include Omnidirectional Blue Dryer Lint Vacuum Attachment, Dryer Vent Brush, Universal Vacuum & Dryer Adapters
• Holikme 58 Pieces 35 Feet Dryer Vent Cleaner Kit, Dryer Cleaning Tools, Include Dryer Vent Brush, Omnidirectional Blue Dryer Lint Vacuum Attachment, Dryer Lint Trap Brush, Vacuum & Dryer Adapters

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The Duct Brush That Actually Clears LG Flow Sense Errors on First Try

Before you order a $300+ blower wheel or moisture sensor, grab a proper duct brush and pull that exhaust line. In my experience, 80% of these Flow Sense alerts disappear after a thorough duct cleaning — and this 12-foot flexible kit reaches deep enough to catch the lint buildup that’s actually triggering the sensor.

What works

• The flexible bristles work through kinks and bends in the exhaust duct without snagging, which matters because this model’s vent routing doesn’t always run straight.
• 12 feet of reach gets you from the dryer all the way through most wall runs and out to the exterior terminator, so you can clean the entire path in one go.
• The bristle design actually scrapes compacted lint off the duct walls — not just pushes it around — which is what you need when you’ve got months of buildup restricting airflow enough to trigger the sensor.

What doesn’t

• If your dryer is venting through rigid metal ductwork with multiple 90-degree elbows, the brush can get stuck — you may need to disconnect sections and work in stages rather than push through end-to-end.
• This isn’t a power tool; you’re pushing and rotating it by hand, so if you’ve got a 25-foot run with heavy lint compaction, expect 20–30 minutes of work and possibly a second person to help feed the brush from the other end.

I can’t tell you how many calls I’ve taken where the homeowner ordered a control board or blower assembly first, only to find out the duct was so clogged lint was basically pouring out once we opened it up. Save yourself the shipping hassle and the wrong diagnosis — start with the duct, and grab a Flexible vent brush kit (12 ft) to do it right.

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