1. Open the vent valve at the highest point of each independent circulating thermal oil pipeline.
2. Start the feed pump of the thermal oil heater and fill thermal oil until oil overflows from the vent valve in the circulating pipeline, then close the vent valve.
3. Stop filling thermal oil when the oil level in the expansion tank is above the low-level mark.
4. Start the circulating oil pump of the thermal oil heater. After the thermal oil circulates in the pipeline for 1 hour, open the vent valve again until oil overflows, then close the vent valve.
5. Check the thermal oil level in the expansion tank. If it is below the minimum mark, start the feed pump again to add thermal oil until the level is above the minimum mark.
