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What improves in the React build (all else equal):
  • Code splitting — only the current page's JS is loaded
  • Image optimization — WebP conversion + lazy loading via React Image
  • CDN caching of static assets via Vercel/Netlify edge network
  • Tree-shaking removes unused CSS and JS from the bundle
  • Prefetching — next pages load before the user clicks

Developer note: Remove this banner and modal entirely from the React production build.

Same-day shipping on in-stock parts ordered by 3 pm CST Mon–Fri · Free diagnosis help: 817.472.7740

Home / Shop / Air Conditioner Parts / 24 volt Transformer MR 50354

24 volt Transformer MR 50354

Other · Air Conditioner Parts

24 volt Transformer MR 50354

Part # MR 50354Sold by U-FIX-IT Appliance Parts

$39.95

In stock
  • Ships same day if ordered by 3 pm CST Mon–Fri
  • 1-year replacement warranty unless stated on your receipt. Warranty & returns
  • Free pickup at Arlington, East Dallas, South Dallas or Tyler
  • Not sure it’s the right part? Free diagnosis help: 817.472.7740
  • Secure checkout

Part details

The 24 volt Transformer MR 50354 (part # MR 50354) is a air conditioner replacement part rated 120 V and replaces This 40 VA transformer can compare to or replace the following popular control power transformers: Global GT4031F, Jard 4031F, Honeywell AT140A1018, AT40A1121, . $39.95 at U-FIX-IT.

Part #MR 50354
BrandOther
ApplianceAir Conditioner Parts
Voltage120 V
ReplacesThis 40 VA transformer can compare to or replace the following popular control power transformers: Global GT4031F, Jard 4031F, Honeywell AT140A1018, AT40A1121, AT40A1139, AT140B1214, Universal UET105, UET115, Steveco / White Rodgers 90-T40F3, Packard PF42440
Price$39.95
Availability34 in stock

Part No. MR 50354

Part Purpose:

The transformer converts high voltage (120 volts or 220 volts) to low voltage (24 volts) used by the wall thermostat to turn the furnace and air conditioner on and off as needed.

Furnace Transformer Specifications:

The MARS-2 Control Transformer 50354 is a 40VA transformer that powers 24 Vac circuits in HVAC systems. This is a NEMA transformer (Class II).

This transformer will replace 24 volt transformers on gas or electric furnaces.  Input voltages of 120 volts, 208 volts or 240 volts may be used with this transformer.

Part failure symptoms:

Both the indoor unit and the outdoor unit fail to come on when thermostat is calling for cooling.

Part diagnosis:

Input voltage measures correctly with multimeter but 24 volts is not present on the output. Bring your “transformer” in for free confirmation that it is good/bad or call the U-FIX-IT store nearest you for free assistance with diagnosis.

Part Location:
Transformer is located inside the furnace near the control board.
Part Replaces:

This 40 VA transformer can compare to or replace the following popular control power transformers: Global GT4031F, Jard 4031F, Honeywell AT140A1018, AT40A1121, AT40A1139, AT140B1214, Universal UET105, UET115, Steveco / White Rodgers 90-T40F3, Packard PF42440.

This 24vac 40VA transformer can be used to replace most 24 volt transformers on furnaces.

Part Specifications:

VA: 40VA
Circuit Breaker: No
Primary Voltage: 120/208/240V 50/60Hz
Secondary Voltage: 24V with Wire Leads
Mount: Foot Mount Transformer
Dimensions: 3.5”³ x 2”³ x 2.25”³

What customers say about U-FIX-IT

Store reviews from ufixit.com. This part has no product reviews on the live site yet product reviews: none on live site

“Honestly I called to check and see if they had a part in stock, and didn’t even end up using them or buying from them, but was just generally impressed with the customer service that I received on the phone. The…”Kirby J · customer review on ufixit.com
“Came in to ask about a part for my washing machine and was assisted by this newer gentleman, Josue. He gave me some great tips for installing and now, thanks to this extremely helpful young man, my washing machine is…”Lisa Panelli-Valentin · customer review on ufixit.com
$39.95

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