4 Reasons to Retrofill Transformers with an Ester Fluid

Ester Fluids Vs Mineral Oils

Many of our customers - transformer retrofillers and transformer service companies, as well as utilities, generators and industrial clients - all want to know if they should be considering ester fluids when they have a transformer that is going to be retrofilled.

It’s a big conversation - there are always different reasons for the retrofill, each transformer is unique and each company has their own decision making process.

Additionally, there are so many advantages to ester fluids to take into consideration, and there is the question of whether synthetic ester or natural ester is the right product for the retrofill in question.

Simplifying the decision making process

In an attempt to give companies a simpler starting point for their decision making, we reviewed the many materials, resources and experience we have in transformer fluids and put together a list of the top 4 reasons to retrofill a transformer with an ester fluid instead of mineral oil.

Four Reasons to retrofill with ester fluids

FIRE SAFETY: reduced risk through much higher fire point and flash point

ENVIRONMENTAL PROTECTION: minimise impact and facilitate compliance


  • Can allow transformers to be located closer together and next to buildings without the need for blast walls.

  • Compliance with AS2067 can be met and insurance premiums can potentially be lowered.

  • MIDEL esters are FM Global approved

TRANSFORMER LIFE EXTENSION: significantly beyond what is possible with mineral oil


Transformer Retrofilling Advice

If you have more questions on the suitability of a natural ester of synthetic ester fluid for a transformer retrofill, don’t hesitate to get in touch with our Customer Service team. We’ll help work through the problem so you are better informed and can make the best decision for the future of your business.