- High thermal efficiency and economical operation.
- Temperatures up to 716°F (380°C), depending on thermal fluid type.
- Water treatment not required.
- Internal corrosion and scale eliminated.
- Freezing risk during winter eliminated.
- Pipe corrosion prevented.
- Nearly maintenance-free operation provided because bellows-sealed valves and simple burner components typically used.
All conventional fuels can be used as well as combustible waste products in solid, liquid or gaseous form, Richardson says, noting that electrical power is the only other external service required. In addition, thermal fluid systems are compact, so they can be placed close to where the heat is needed, minimizing the need to alter the building and shortening installation time.
Modern thermal fluids offer good thermal stability and heat transfer characteristics to ensure long life and low viscosity for good circulation. The thermal fluid typically circulates through the heater coils via a low-pressure circulating pump selected for high temperature operation. Three-way control valves regulate temperature while safety systems monitor the flow and return temperatures, and automatically adjust burner firing, Richardson says.
Thermal fluid heaters use an expansion tank that allows thermal fluid expansion during operation, and the release of water vapors and gases during startup and throughout the life of the system. Pipework to and from the system should be carbon steel with suitable expansion devices and cast iron bellows-sealed valves, which are welded in position to eliminate gasket joints. This reduces the risk of leakage at flanged joints, which should be kept to a minimum, Richardson says. After installation all pipework should be insulated and clad. For more information, visit www.thame-energy.com.