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Supco Tradefox Jumper King Bypass Low Voltage Thermostat to Activate The Circuit

  • Based on 311 reviews
Condition: New
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Availability: 18 left in stock
Fulfilled by Amazon

Arrives Oct 11 – Oct 13
Order within 4 hours and 10 minutes
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Features

  • Quickly bypass thermostats and activate HVAC circuits for fast troubleshooting and system diagnostics.
  • Includes interchangeable adapters such as magnetic tips, alligator clips, spade connectors, and self-piercing insulation probes.
  • Ideal for testing compressors, relays, contactors, and thermostat circuits during AC or heat pump service.
  • Designed for use on 030V HVAC control circuits with built-in resettable fuse protection.
  • Comes with 20 interchangeable ends and a durable zip-up carrying case for organized field service.

Description

Supco Tradefox's Jumper King Multi Jumper with Selector One hookup allows you to safely bypass any low voltage thermostat and activate the leads/circuit of your choice. Eliminates compressor short cycling and start the system safely when your ready to start it Innovative circuit selector switches to activate leads/circuits of your choosing at any timeResettable popper fuse - will never short outNo batteries required - powered by the low voltage in the A/C unitWorks on multi stage units including heat pumpsIncludes 20 interchangeable ends2 Spade Adapter6 Alligator Clamps6 Magnetic Tips6 Self Piercing Insulation Tips6 Jumper Leads1 Hard Zip-Up EVA Sectioned Case1 Jumper King Thermostat Bypass ToolEquipped with Magnets and Fold-Out Hook for Hands Free Work

Brand: Supco


Style: Compact


Color: Orange


Item Weight: 0.78 kg


Min. Operating Voltage: 1 volts


Minimum Operating Voltage: 1 volts


Upper Temperature Rating: 150 °F


Measurement Type: Voltmeter


Compatible Devices: HVAC systems, heat pumps, air conditioners


Style Name: Compact


Color: Orange


Item Weight: 0.78 kg


Specification Met: CE


Brand Name: Supco


Model: TFXJK


Unit Count: 1 Count


UPC: 687152291489


Number of Items: 1


Manufacturer: Supco


Part Number: TFXJK


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Oct 11 – Oct 13

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • Helped me!
Found defrost broad was the reason for wires melting together. Being able to start the unit with confidence, and seeing and hearing the unit at start makes the deference. Can by used in many other low volt tests.
Reviewed in the United States on April 2, 2026 by Look1ng2

  • I use this all the time at my HVAC job
Great tool to troubleshoot 24v problems easy to understand too
Reviewed in the United States on July 25, 2026 by Jonathan Martinez

  • Definitely
Must buy if you're in HVAC. Super easy to find shorts
Reviewed in the United States on June 20, 2026 by Nick

  • Trade Fox Low voltage bypass
Works great for bypassing HVAC thermostat.
Reviewed in the United States on March 22, 2026 by Amazon Customer

  • Great tool addition
Saves time and money. Love it
Reviewed in the United States on November 19, 2025 by Gaza

  • A must have!
Can’t express the appreciation I have it for this device, it really saves you time when working.
Reviewed in the United States on April 4, 2026 by ORubio89

  • Works
Well, the first one came with a broken toggle switch, second one not. Works as it should. Of course though, wish I would have waited for the new version of this, the switches seem more sturdy and thought-out on that model, or maybe this model just being the first of it was money saving option for production. Either way, buy the new version and not this one lol . ... show more
Reviewed in the United States on February 14, 2026 by shane cody

  • Awesome Purchase
Awesome Purchase
Reviewed in the United States on April 16, 2026 by :-)

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