How to replace the flapper door and mullion heater WP12722803W on a Whirlpool fridge

Struggling with a Whirlpool refrigerator that refuses to keep its cool due to a faulty flapper door or a burnt-out mullion heater? Don’t worry; we’ve got you covered with a straightforward, cost-effective DIY fix that spares you the expense of hiring a pro. Scroll down to check out our step-by-step how-to video and get your fridge back in top shape in no time!

Are you experiencing issues with your Whirlpool refrigerator’s flapper door? Maybe the hinges are broken and preventing the French doors from closing correctly or the mullion heater has burned out and caused extra condensation buildup.

Whatever the issue is, we’re here to help you replace it. This is an easy DIY repair that will save you the hassle and cost of calling a professional.

You can find a replacement flapper door with a mullion heater here. If you need other replacement parts for your Whirlpool refrigerator, just enter your model number at AppliancePartsPros.com to find them. It’s that easy! Most orders arrive in just two business days, and we have thousands of guides to show you how to install your new parts.

WATCH: How to replace flapper door and mullion heater on a refrigerator

What is the flapper door and mullion heater?

The flapper door is mounted on a portion of the left-side French door and serves as a latch to keep the door closed. It also has three hinges that allow it to rotate 90 degrees so the French doors open and close smoothly. The flapper door works with the mullion heater to prevent moisture and frost from forming on the refrigerator’s exterior.

Embedded within the flapper door is the mullion heater, which sits between the fridge and bottom freezer compartments. It helps prevent condensation buildup, which can lead to mold growth, unpleasant odors, and potential damage to your refrigerator’s interior. The mullion heater provides gentle warmth to prevent moisture from accumulating on the flapper door’s surface.

If your mullion is bad, you’ll notice moisture building up on the flapper door.

When either the flapper door’s hinges break or the mullion heater burns out, it’s time to replace the entire assembly to restore proper functioning and prevent further issues.

What you need

• 1/4-inch nut driver
• New flapper door with mullion heater (make sure it’s compatible with your specific fridge model BEFORE installing!)

READ MORE: How To Clean Refrigerator Coils

Keep safety first

When working on any appliance, remember to keep safety first. Here are some tips to keep in mind:

• Always power off and unplug your appliance or switch off the circuit breaker before attempting maintenance or replacement work. This keeps you safe by preventing any risk of electric shock.
• Turn off the water supply at the outlet before beginning repairs. Keep towels ready to catch any residual water in the system when removing parts.
• If the appliance has recently been used, give it plenty of time to cool down before working on it.
• Take your time while working to prevent accidents and personal injuries. Rushing is the enemy of precision.
• Work in a well-lit area so you can clearly see and access appliance parts.
• Keep your workspace free of clutter and other obstacles. Keep children and pets away from the work area.
• Never work on internal parts with wet hands. Make sure the work area is completely dry.
• Check the user manual to see if there are specific installation or safety instructions related to your appliance or replacement part.
• Be gentle when handling or removing parts. Excessive force might damage the appliance or cause personal injury.
• Wear insulated work gloves to protect your hands from sharp metal parts and debris.
• When working with wires, avoid touching any exposed wires or terminals. If you need to touch a wire, use a non-conductive tool or wear insulating gloves to prevent electrical shock.
• Consider wearing safety glasses and/or a dust mask when working with chemicals, dust or a large amount of debris to prevent irritation or injury.

READ MORE: A Complete Guide to Refrigerator Organization

How to replace the flapper door with a mullion heater

1. Turn off the fridge and unplug it from the power source.
2. Open the left-side French door of your refrigerator.
3. Find the flapper door and open it. This will expose the hinges and the electrical connection for the mullion heater.
4. Use a 1/4-inch nut driver to remove the single screw that holds the central hinge of the flapper door.
5. Gently push the flapper door upwards to disengage all three hinges from their respective mounting points. Be very careful during this step to avoid damaging the hinges or other surrounding parts.
6. Carefully turn the flapper door and remove it from the refrigerator.
7. Find the electrical plug that powers the mullion heater on the old flapper door. Press the locking tab and gently pull the plug to disconnect it from the refrigerator’s wiring harness.
8. Plug the electrical connector for the new mullion heater into the refrigerator’s wiring harness.
9. Carefully align the three hinges on the new flapper door with their respective mounting points on the refrigerator door. Make sure the hinges are facing the correct direction and the flapper door is positioned correctly.
10. Use the 1/4-inch nut driver to put the screw you removed earlier into the central hinge of the new flapper door. Tighten the screw but don’t over-tighten it.
11. Close the new flapper door and close the left-side French door.
12. Plug the refrigerator back into the power source or turn the circuit breaker back on.

READ MORE: 7 Space-Saving Tips For Small Kitchens

More information

Thanks for reading! We hope this guide helped you replace the flapper door with a mullion heater in your Whirlpool refrigerator.

If you still need some replacement parts, grab your model number and head over to AppliancePartsPros.com. We offer over two million parts and most orders arrive in two business days. If you need some help with finding the right part or placing an order, you can contact our team at 1 (877) 477-7278.

While you’re waiting for your new part to arrive, you can explore our DIY blog and watch thousands of video tutorials on our YouTube channel. We can also help you troubleshoot common fridge problems here.

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