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Lennox 73W20 Limit Switch L175-30F 175°F Open-on-Rise 5" OAL

Lennox 73W20 Limit Switch L175-30F 175°F Open-on-Rise 5" OAL

Low stock: 2 left

Regular price $65.00 USD
Regular price Sale price $65.00 USD
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Key Features & Specifications

  • Genuine Lennox OEM L175-30F limit switch ensures system safety and reliability.

  • Actuates (opens circuit) at 175°F and automatically resets at 145°F.

  • Durable metal construction designed for longevity in industrial HVAC environments.

  • STILT surface mount design with standard screw terminals for easy installation.

  • Essential safety device compatible with a wide range of Lennox, Armstrong, and Ducane furnaces.

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Specifications

Feature Specification
Model Number L175-30F
Switch Action Open On Rise
Opening Temperature 175°F
Reset Temperature 145°F
Overall Length (OAL) 5 inches
Mounting Type STILT (Surface Mount)
Terminal Type Screw
Reset Type Automatic

description

 Lennox 73W20 Limit Switch L175-30F 175°F Open-on-Rise 5" OAL

The Lennox 73W20 is a genuine OEM limit control switch (L175-30F) designed for use in Lennox, Armstrong, and Allied Air furnaces. This critical safety component monitors the temperature within the heating system and automatically interrupts the electrical circuit if the temperature exceeds a safe limit, preventing overheating and potential damage to the heat exchanger. 

Key Features:

  • Safety Assurance: Designed to open the circuit precisely at 175°F to protect the furnace from dangerous overheating conditions.
  • Automatic Operation: Features an automatic reset function, allowing the system to resume operation once the temperature drops to the safe threshold of 145°F.
  • Durable Construction: Built with rugged metal materials to withstand the demanding thermal environment of a furnace.
  • Direct OEM Fit: Engineered for direct compatibility with numerous Lennox HVAC systems, simplifying installation and ensuring proper functionality. 

Product Details:

  • Feature: Specification
  • Model Number: L175-30F
  • Switch Action: Open On Rise
  • Opening Temperature: 175°F
  • Reset Temperature:145°F
  • Overall Length (OAL): 5 inches
  • Mounting Type:   STILT (Surface Mount)
  • Terminal Type: Screw
  • Reset Type: Automatic

🛠️ HVAC Depot Pro Tip:

A faulty limit switch is a common cause of a furnace that cycles on and off repeatedly ("short cycling"). If your furnace is short cycling, use a multimeter to test continuity on this switch after the furnace has been running for a few minutes. If it opens prematurely (below 175°F), the switch is defective and requires replacement. 

Cross-Reference:

  • Manufacturer: Lennox / Armstrong / Allied Air
  • Drawing/X Numbers: 102857-07
  • Legacy Numbers: 73W2001, 68J28, 68J2801, R102857-07 

Model Compatibility:

This safety switch fits numerous popular Lennox models, including: 

  • EL195UH045XE36B-01
  • ML193UH045XP36B-59
  • LRP13GXK36-072-01
  • Various G-series and residential air handler units

Specification

Refund policy

Refund & Return Policy

Last Updated: June 2026

At HVAC Parts & Equipment Depot, customer satisfaction is important to us. This Refund & Return Policy explains how returns, exchanges, and refunds are handled for purchases made through TopHVACParts.com.

Return Eligibility

We accept returns within 30 days of delivery.

To qualify for a return:

  • The item must be unused, uninstalled, and in its original condition.
  • The item must be returned in its original packaging.
  • Model numbers and serial numbers must match the original purchase records.
  • Proof of purchase or order confirmation is required.

Non-Returnable Items

The following items are not eligible for return or refund:

  • Installed or used parts.
  • Products showing signs of installation, modification, or damage caused after delivery.
  • Items missing original packaging.
  • Sale or clearance items.
  • Special-order or custom-order products.
  • Returns requested more than 30 days after delivery.

Restocking Fee

Approved returns may be subject to a 20% restocking fee.

The restocking fee will be deducted from the refund amount after the returned item has been inspected and approved.

Damaged, Defective, or Incorrect Items

If you receive a damaged, defective, or incorrect item, please contact us within 7 days of delivery.

Email: support@tophvacparts.com
Phone: (214) 734-5222

We may request photographs and additional information to help process your claim.

If the claim is approved, we will provide a replacement, exchange, or refund at no additional cost to you.

Exchanges

We replace items only if they are defective, damaged upon arrival, or incorrectly shipped.

To request an exchange, contact us at:

support@tophvacparts.com

Refund Process

Once your return is received and inspected, we will notify you by email regarding approval or rejection of your refund request.

If approved:

  • Refunds will be issued to the original payment method.
  • Processing typically takes 7–14 business days after approval.
  • Your financial institution may require additional time before the refund appears in your account.

Return Shipping

Customers are responsible for return shipping costs unless the return is the result of:

  • Our shipping error,
  • A defective product,
  • A damaged product received upon delivery.

Original shipping charges are non-refundable.

We recommend using a trackable shipping service and purchasing shipping insurance for higher-value items.

Return Address

HVAC Parts & Equipment Depot
1135 E Plano Parkway, Suite 8
Plano, TX 75074
United States

Professional Installation Notice

Many HVAC products require installation by a licensed HVAC professional.

HVAC Parts & Equipment Depot is not responsible for damages resulting from improper installation, misuse, unauthorized modifications, or failure to follow manufacturer instructions.

Special Orders

Special-order products must be picked up within 30 days of purchase unless other arrangements have been approved.

Unclaimed special-order products may be returned to the manufacturer and may be subject to applicable restocking fees.

Contact Us

If you have questions regarding returns, refunds, or exchanges, please contact us:

HVAC Parts & Equipment Depot

Phone: (214) 734-5222
Email: support@tophvacparts.com

Michel & Siso are very knowledgeable and explain everything to where I could understand! Amazing experience! Thank you will always come here for any AC needs. Trustworthy and excellent customer service.

Celest G.
Verified Customer
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