Skip to main content
Expedited shipping available at checkout

Zinsco QC20 Molded Case Circuit Breaker

  • 20A
  • 2 Pole
  • Plug-On
Zinsco QC20
Molded Case Circuit Breaker
Brand Zinsco
SKU QC20
Select Item Condition
Earn 49 SuperPoints
  • 20A
  • 2 Pole
  • Plug-On

Quantity

Bulk Pricing
Send your parts list for a volume quote.
Zinsco QC20 2 Pole Circuit Breaker

Zinsco QC20 - 20A 2 Pole Molded Case Circuit Breaker

Re-Certified

$49.70 In Stock

Quantity

Similar Items

Description

Built to maintain older electrical systems, this 20A two-pole breaker delivers dependable long-time and instantaneous trip functions for everyday loads. It integrates seamlessly into original Zinsco panelboards, offering a precise physical fit without modification. This component acts as a substitute for the UBIZ220. Rated for 10kAIC at 120/240VAC, the breaker includes HACR and SWD certifications, ensuring safe operation for air conditioning equipment and fluorescent lighting circuits.

Specifications

Key specifications
Brand Zinsco
Part Number QC20-R
Series QC
Amperage 20A
Poles 2
Mounting Style Plug-On
Voltage 120/240VAC
Phase 1
AIC Rating 10kA @ 120/240VAC
Fit and installation
Frame Type QC
Terminal Type Lugs
For Use With Zinsco Load Centers
Wire Gauge 14-6 AWG
Max Wire 6 AWG
Min Wire 14 AWG
Protection and operation
Trip Technology Thermal Magnetic
Trip Function Code LI
Trip Function Long-Time, Instantaneous
Trip Adjustability Fixed
Standards and features
Standards UL 489
Approval UL
Temp Rating 40C
Construction Features HACR Rated, SWD Rated

Product FAQs

6 answers
What panels are compatible with the Zinsco QC20 circuit breaker?

The QC20 is designed for use in vintage Zinsco and Sylvania load centers that accept type QC plug-on breakers.

Is there a modern replacement available for the Zinsco QC20?

Yes, Connecticut Electric manufactures a direct replacement for this breaker under the catalog number UBIZ220. It provides an exact physical fit for original Zinsco panels without requiring adapter kits.

Are there known safety concerns with older Zinsco circuit breakers?

Yes, vintage Zinsco panels and breakers have a documented history of safety issues. Common problems include breakers failing to trip during overloads, breakers welding to the bus bar, and bus bar corrosion. These issues can lead to overheating and fire hazards, prompting many electricians to recommend full panel upgrades.

How does the QC20 breaker connect to the panel?

The QC20 features a plug-in connection. It hooks under the hold-down tab in the panel and presses down so the plug-in clip slips securely over the bus bar stab. Ensure main power is disconnected before installation.

What types of loads is the Zinsco QC20 suitable for?

As a 20A, two-pole breaker, the QC20 is typically used for 240V residential or light commercial applications. Common uses include baseboard heaters, small well pumps, and large window air conditioners.

Can I use the QC20 in a modern electrical panel?

No, the QC20 is specifically designed for legacy Zinsco and Sylvania load centers. It will not fit or function safely in modern panels from brands like Square D, Eaton, or Siemens.

SuperClub

Join free. Get 500 SuperPoints.

Earn points on eligible purchases and redeem them at checkout.

100 SuperPoints = $1 off.

Warranties

60-Day Warranty

Your purchase includes 60 days of SuperBreakers warranty coverage.

Get a Quote

Don’t see what you’re looking for?

We source obsolete and hard-to-find parts every day.

Shipping

Free Shipping Policy

Parcel shipments with item value over $99 qualify for free economy shipping within the continental US. Please call to confirm special handling instructions. We do not charge a handling fee or require a minimum amount on any order. SuperBreakers does not ship on customer accounts.

Read our full shipping policy

Same Day Shipping

We strive to ship out your items the same day the order is placed. In rare circumstances SuperBreakers may reserve up to 5 business days to consolidate orders for complete shipment.

Expedited Shipments

Orders being shipped via Next Day Air, 2 Day Shipping or 3 Day Shipping must be received by 3 PM EST to guarantee same-day shipments. Expedited orders only ship on normal business days. Shipments will NOT be sent out on Saturdays and Sundays.

International Shipping

All International orders require a $1,000 minimum order threshold. Due to the special nature of these shipments, we require that these be placed with a SuperBreakers representative. Additional shipping and instructions will apply. All International Orders are Non-Cancel and Non-Refundable.

Reviews

5.0
Rated 5.0 out of 5 stars
Based on 15 reviews
Total 5 star reviews: 15 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
Rating
Ratings
15 reviews
  • DS
    Denise S. A.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer QC3070H - 70A 3 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/4/25
    Great turn around!

    My experience was great. I had the item quickly; and it was more reasonably priced than other places I checked. Not having to pay freight was an absolute bonus.

  • DM
    Douglas M.
    Verified Buyer
    Reviewing
    Eaton / Cutler-Hammer QC1020 - 20A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    7/28/25
    Just what I needed

    Ordering was easy and the processing was immediate. The beakers I ordered was exact. I recommend this company for your needs.

  • GL
    Gianna L.
    Flag of United States
    Reviewing
    Eaton / Cutler-Hammer QC1015 - 15A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    11/27/23
    Great

    as advertised!

  • ED
    Elmer D.
    Flag of United States
    Reviewing
    Zinsco QCAL100 - 100A 2 Pole Molded Case Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    10/28/23
    Very accurate, delivered on time

    Very accurate, delivered on time and fixed my problem good job

  • RB
    Rawle B.
    Flag of United States
    Reviewing
    Eaton / Cutler-Hammer QC1015 - 15A 1 Pole Miniature Circuit Breaker
    I recommend this product
    Rated 5 out of 5 stars
    8/8/23
    SuperBreakers had the parts I

    SuperBreakers had the parts I needed in stock, was shipped and delivered on time. Great service!