Harford 3-Sided Dart-Mounted Magnetic Gasket – Walk-In Door OEM Replacement

Harford 3-Sided Dart-Mounted Magnetic Gasket is a replacement walk-in cooler and freezer door gasket listing for commercial equipment where the technician needs to match the gasket by size, hand, side count, and part number before ordering. This product uses a dart-mounted magnetic profile, meaning the gasket is designed to press into a matching retainer channel on the door and use its magnetic edge to help pull the door closed against the frame.

A walk-in gasket is more than a strip of rubber around the door. It is part of the temperature-control system. When the gasket seals correctly, the box keeps cold air inside, reduces warm-air infiltration, limits frost buildup, and helps the refrigeration system maintain set point without unnecessary run time. When the gasket is torn, hardened, compressed, pulled loose from the dart track, or no longer magnetically gripping the frame, the equipment can lose temperature, build frost around the door opening, and force the evaporator, compressor, and controls to work harder than they should.

What This Gasket Does

This gasket seals the perimeter of a walk-in door. The dart portion anchors into the door channel, while the magnetic sealing face meets the door frame when the door closes. The listed variants include left-hand, right-hand, and 4-sided size options, so the correct choice depends on the door opening, hinge orientation, gasket profile, and the number stamped or documented for the original part.

Available SKU / Size Options

• LH770134 - 35-1/2" x 77" left-hand
• RH770134 - 35-1/2" x 77" right-hand
• D3476 - 36" x 79-1/2" 4-sided
• LH770136 - 37-5/8" x 77" left-hand
• RH770137 - 37-5/8" x 77" right-hand
• 500000067 - 37-3/4" x 79-1/4" 4-sided
• 2261910 - 38" x 79" left-hand
• 2261910R - 38" x 79" right-hand
• 770138 - 49-3/8" x 83" left-hand

Common Signs a Walk-In Door Gasket Needs Replacement

• Visible tearing, cracking, compression, or pulled corners
• Warm air leaking around the door edge
• Frost or ice forming near the door frame
• The door closes but does not seal evenly against the frame
• The magnetic edge feels weak, distorted, or separated
• The refrigeration system runs longer because cold air is escaping
• Food storage temperature becomes harder to maintain during busy service periods

How to Verify the Correct Gasket

Before ordering, compare the selected SKU, gasket dimensions, hand orientation, number of sides, dart profile, and magnet position against the gasket being removed. Measure the existing gasket from outside edge to outside edge, confirm whether the door requires left-hand or right-hand construction, and check whether the original part is 3-sided or 4-sided. Photos of the gasket profile, door channel, corners, and serial plate can help confirm the correct replacement.

Related Parts to Inspect

A gasket failure can be caused or worsened by other door hardware issues. When replacing this gasket, inspect the hinges, door closer, latch, strike, sweep, frame heater where applicable, door alignment, and retainer channel. If the door sags, the latch does not pull the door tight, or the frame is damaged, a new gasket may not seal correctly until the related hardware problem is corrected.

Commercial Service Notes

This listing is intended for commercial walk-in cooler and freezer repair. Restaurants, commercial kitchens, foodservice operators, supermarkets, convenience stores, and service technicians should verify the OEM/SKU and measurements before ordering. PartsDirectOnline ships commercial refrigeration parts throughout New York, New Jersey, Connecticut, the Tri-State area, and the United States.

FAQs

What is a dart-mounted magnetic gasket?

A dart-mounted magnetic gasket has a mounting rib that presses into the door gasket channel and a magnetic sealing face that helps the gasket hold against the metal door frame when the walk-in door closes.

Why does the hand orientation matter?

Some walk-in door gaskets are built for a specific left-hand or right-hand door layout. Match the selected variant to the original gasket and door swing before ordering.

How should I measure this gasket?

Measure the existing gasket from outside edge to outside edge, then compare that measurement to the variant size. Also verify the dart profile and whether the gasket is 3-sided or 4-sided.

Can a bad gasket cause frost around a walk-in door?

Yes. A leaking or damaged gasket can allow warm, humid air into the box. That moisture can freeze around the door opening and increase load on the refrigeration system.

What should I check if the new gasket does not seal evenly?

Check door alignment, hinge wear, latch adjustment, door closer operation, frame condition, and the gasket retainer channel. A hardware or alignment issue can prevent even a new gasket from sealing properly.

What information should I have before ordering?

Have the SKU or OEM number, gasket dimensions, hand orientation, door model or serial plate when available, and clear photos of the old gasket profile and door channel.