Minimize the time and cost associated with starting up a thermal fluid heater system by completing a checklist of things to do before the field engineer’s on-site arrival.

Water should not be used for testing because the system should be as dry as possible before filling.

Consider an organized, orderly approach to shaving time and dollars off your thermal fluid heater system startup. Tedious? Yes. Worthwhile? Absolutely.

Following a detailed checklist for system startup before the manufacturer’s field engineer arrives at your site helps keep everyone from dragging out the process. Thermal Fluid Systems Inc., Kennesaw, Ga., recommends that your checklist contains these items.


  • So that any leaks may be indentified easily, do not insulate the process piping until after completion of initial system heatup.
  • Has all equipment been installed, and has the piping been completed in accordance with the drawings, good engineering practices and applicable codes?
  • Has the associated process piping been cleaned, pressure-tested and/or leak-tested? Remember that water should not be used for testing because the system should be as dry as possible before filling.
  • Does the system have sufficient vent and drain valves installed for filling, venting and draining the system?
  • What type of thermal oil will be used?
  • Has the system volume been determined, and is there a sufficient amount of the selected thermal oil available on site?
  • Are required utilities such as nitrogen, carbon dioxide, water, steam or atomizing air available for use during startup and operation?


  • Has the field wiring been completed in accordance with the drawings, good engineering practices and any applicable codes?
  • Has the electrical power been connected to the control panel with sufficient capacity and protection per good engineering practices and applicable codes?
  • Do the flame scanner wires run in a separate conduit and are they wired directly to the flame safeguard wiring base?


  • Is the gas pressure at the inlet of the gas train in accordance with the design requirements? What is the actual pressure reading?
  • Has the gas train been installed and properly vented according to the manufacturer’s recommendations, good engineering practices and applicable codes?
  • If fuel oil is being used, does the fuel oil tank have an adequate supply available for startup?
  • If the pilot fuel is supplied from a separate source, is there sufficient fuel available for startup and operation?


  • Are there any components that have been damaged in shipment or during installation?
  • Are there any components that are missing?
  • Are all the heat users ready to be commissioned and accept fluid flow and heat?
  • Are there any temperature restrictions associated with any of the users that would limit the commissioning temperature of the heating equipment?
  • Will a process load be available, preferably at 100 percent capacity, to properly tune and adjust the controls and burner?
  • Are operation and maintenance personnel available to assist with startup and receive training in operation, maintenance and troubleshooting?

Additional Checks and Information

  • Ensure that the exhaust stack area is not any smaller than the breech opening to avoid allowing a backpressure to build up on the heater. Be sure the stack is designed and installed according to good engineering practices and applicable codes.
  • Check that all RTDs are operational. The resistance should be 100 Ω at 0°C. At ambient temperature, it should be approximately 110 Ω.
  • Remove and check that the flowmeter sensing tubes are clear of any blockages. Blowing air through them is an adequate check. If needed, replace the tubes with steel tubing. Do not use copper tubing as a replacement because copper reacts with thermal fluid. If needed, you can obtain replacement ferrules through the manufacturer.
  • Clean out the expansion tank, blocking vessel and gas/dirt separator prior to installation into the system.
  • Check that the pump strainers are clean prior to filling the system.
  • Ensure there is access to the top of the expansion tank. You must be able to get to the top to remove the blind flange during the thermal oil-conditioning phase to allow water vapor and entrapped gases to leave the system.

Thermal Fluid Systems Inc., Kennesaw, Ga., is a manufacturer of thermal fluid heating systems for industrial applications. For more information, call (770) 425-5556; e-mail or visit