Retrofilling
Retrofill New Life Into Your Transformer with FR3®
Experience the FR3® Difference
There is no better, faster, and safer way to upgrade your existing mineral oil-filled transformers than to retrofill with FR3 fluid from Cargill. FR3 is the industry-leading natural ester alternative option for your transformer dielectric insulating liquid. Discover the benefits for you and the environment when you upgrade your transformer fleet with FR3.
Ready to retrofill with FR3? Request a quote for a more precise estimate tailored to your transformer fleet needs.
4 Reasons to Retrofill with FR3:
Extend asset life
- 50% – Maximum anticipated asset life extension
- +10 – Years of life added to the transformer
- 10x – Higher moisture content by comparison
Increase load capacity
15% – Additional loading or load capacity of existing transformers.
Improve fire safety and equipment resiliency
- 0 – Reported Fires in 25+ years
- 2x – Mineral oil’s flash and fire points
Decrease environmental impact
- 10 – Minimum number of days for biodegradation
- 0 – Carbon neutral
Safe, Compliant Retrofilling Services
Choosing FR3 natural ester fluid for your distribution and power transformers has long-term safety, reliability, and environmental benefits. As an Authorized Service Partner of FR3 fluids from Cargill, SDMyers is equipped to help you extend the service life of your transformers by up to 10 years through a retrofill process.
See the Differences: FR3 vs. Mineral Oil *
Mineral Oil
FR3
* Technical information on FR3 is sourced from Cargill (FR3 manufacturer). For additional resources and information on FR3, please visit cargill.com.
** “Non-toxic” classification for FR3 fluid and Envirotemp 360 fluid is according to IEC6770 requirements and the revised EPA definition. “Non-hazardous in water and soil” classification for FR3 fluid Envirotemp 360 fluid is according to GHS.
*** See OECD 301 B (Readily) and Environmental Protection Agency OPPTS 835.3110 (Readily) and 835.3100 (Ultimately)
Certifications & Partnerships
Powered by industry-respected accreditations, certifications, and partnerships to deliver accurate testing, sound diagnostics, and safe fieldwork.
Free Download for Transformer Owners
Quick Guide to Retrofilling with FR3®
Retrofilling your distribution and power transformers with FR3 fluid provides several benefits to both your bottom line and the communities you serve. Choosing FR3 natural ester fluid for your distribution and power transformers has long-term safety, reliability, and environmental benefits. As an Authorized Service Partner of FR3 fluids from Cargill, SDMyers is equipped to help you see up to 10 years of additional life for your transformers from a retrofill process.
Learn more about retrofilling services from SDMyers and our recommendations to help maximize the reliable life of your transformer.
Download the Free Quick Guide to Retrofilling with FR3
Download - Retrofilling with FR3
Resources
We’re the transformer experts so you don’t have to be. Explore resources backed by 60+ years of end-to-end transformer care experience and diagnostics data.
Frequently Asked Questions
Retrofilling is the process of replacing the existing mineral oil in a transformer with a high-performance alternative fluid — most commonly natural ester fluid like FR3®. This upgrade enhances safety, extends asset life, and improves overall transformer performance without requiring full equipment replacement.
FR3 is a natural ester dielectric fluid made from plant-based oils. Compared to traditional mineral oil, it offers:
- Significantly higher fire and flash points
- Biodegradability and non-toxicity
- Improved moisture tolerance
- Reduced insulation aging
This results in better reliability and safer operation.
Most distribution and power transformers are good candidates, but suitability depends on:
- Transformer condition and age
- Insulation health
- Design compatibility
A condition assessment and oil analysis are typically performed first to determine eligibility.
Retrofilling significantly improves environmental sustainability:
- FR3 fluid is biodegradable (in as little as ~10 days)
- Non-toxic to soil and water
- Derived from renewable resources
This makes it ideal for environmentally sensitive locations.
Retrofilling can improve long-term reliability and slow insulation aging, but routine maintenance and oil testing are still essential. Updated test packages are typically recommended post-retrofill.
Used mineral oil is safely removed, handled, and disposed of or recycled in accordance with environmental regulations and industry best practices.
Yes. Nameplates and labeling are updated to reflect the new fluid type and, if applicable, adjusted ratings (such as K-factor). This ensures compliance and proper identification.
The best first step is a professional assessment. This typically includes:
- Field inspection
- Laboratory oil analysis
- Data-driven diagnostics
From there, you’ll receive a recommendation tailored to your assets and operational goals.
Talk with a Transformer Expert
Get a free quote or consultation—we’re here to help.
Call (330) 630-7000 or fill out the form to connect with an SDMyers transformer expert today.
