Island City

Mill Log Group of Companies is your Island City Authorized Distributor

The Dynamic Heat Generator (DHG) was first developed in 1999. Its roots can be traced back to the oil field market where it was first used to maintain diesel engine temperatures during idle. As applications continued to evolve, and the need for more heat increased, the oil field service sector requested larger models to create more heat, which were primarily used in Nitrogen and Fracturing pumpers being operated throughout the industry. With a robust construction, fast heat rise and overall superior performance, the heaters offered the oil field market a product that was easy to gain trust in.

With its instant success, the heater’s list of applications expanded beyond just engines. DHG Heaters have been used in a variety of settings for many different types of fluid and air heating. As popularity increased, DHG Heaters have steadily been replacing fuel style boilers with units that were not only more efficient, but also easier to package due to their compact size and flexibility of input and output drive options.

The Dynamic Heat Generator (DHG) creates heat by shearing the fluid. With that understood, the next step is to understand some of the basic applications. Since this is an engineered product, all applications are per review. The heater in general is powered by rotational input, such as an electric motor, combustion engine, turbine, windmill, or similar device.

What is nice about the physical external layout of the DHG is that it is configured in various SAE pump mount styles, which include mounts A – F on input (drive) and through drives (output drives) A – D. With these mounts, it is easy to mount to an electric motor (TC Mount) via a pump motor adapter, or to a combustion engine via the pump drive plate, or to a gear box pump mount. While these are all standard models, we will also configure units to special electric motor mounts or that are flywheel mounted on combustion engines. Island City’s DHG has the flexibility to adapt to or configure other style mounts as needed. We love ways to heat, so please bring your new application to us!

Once rotary motion is acquired via the prime mover and fluid is present, shearing occurs to create heat. Fluid flowing through the unit carries heat away to the point of use. The heated fluid can be transmitted to a variety of “sources” such as a distribution manifold for in-floor tubing to heat a building or it can go directly into an engine block to pre or post heat an engine. In addition, the fluid can travel to fluid sumps to heat lubricant in a gear box or hydraulic tank, as well as heat transfer fluid, water, refined foods, or ??, the list goes on and on! One important point is that typically, the heated fluid does not need to go to a heat exchanger as it is heated directly–saving a component in your heating system and resulting in a significant cost savings.


The DHG continues to expand into new markets. Its ability to heat fluids directly, have quick heat rise and have an excellent heat recovery make the DHG sought after. With over 48 different models, the DHG sets itself apart by being able to produce heat with a multitude of fluids in an array of temperature bands.

Island City’s Dynamic Heat Generator(DHG) continues to break new ground in the shear heating market and has lead the company to become an “Industry Standard” in shear heating. In addition, Island City is now the – Largest Manufacturer of Dynamic Heaters in the World.

Customer Testimonials

The units are amazing, your ability to size the units so close allows us to hone in to the best efficiency of the engine, “Your units are near an engine/governor.”

TIM A. Minneapolis, MN

We are impressed, a unit just came back after 8 years in service. “The units just run and run, the engine control simply turns it on when needed.”

Moscow, Russia

When we spec equipment it needs to be rugged and reliable for offshore drilling. The Dynamic Heat Generator meets the demands that a lot of people just can’t understand. Your DHG’s are the best of the best. The “industry standard” for a reason–“because they work”.

Gulf of Mexico, Mexico

Your units are very robust and work well. We wish other products would work like yours.

Beijing, China

Offshore drilling is literal another world, when you have problems out here you are alone. Quickly you learn what you can trust for products and materials. We have high confidents in the DHG’s because they simply run without problems.

Baton Rouge, LA