1. During initial start-up and after extended shut downs (maintenance periods, breakdowns, or holidays, etc...), the control instrument must be manually controlled through the High Limit thermocouple within the radiant tube or element chamber. Maximum allowable increase per hour as sensed by the heating element control thermocouple should not exceed 500 F. per hour up to 1000 F, and only 100 F per hour thereafter until furnace operating temperature is obtained. Without careful control of element temperature, over-temperature conditions will occur, causing sagging, distortion, and rapid fatigue leading to melting.
2. Use a high quality pyrometer, and be sure safe operating conditions are NOT exceeded. Make sure that the T/C's are functioning and in proper position at all times the equipment is in operation.3. The thermocouple used to control the Firebar should be within the radiant tube, minimum of 1/3 third down the effective heater length. Remember the greater the distance the T/C is from the element, the greater the lag time in temperature readings.
3. Sometimes excessive temperature is caused by furnace control couple calling for heat too rapidly. Batch loaded furnaces with doors are the most likely type to have this condition. Controller must be set to specific rate to prevent overheating of elements.
4. When a burnout occurs, either due to normal use or excessive temperature, the metal in the center of the wire melts first and may run out and the end will be hollow, this is not a defect, at the point of breakage there will always be a sign of fusion.
5. Turn off and secure disconnects for all power to the electrical devices being worked on. Wear safety glasses and insulating gloves.
6. Heat generated by electric heating elements will cause bolted terminal connections to expand and loosen. Retighten connections after initial furnace start-ups or installation of new elements. Periodic tightening of buss bars, transformer lugs, and element connections will prevent downtime for equipment repair. Do NOT continue to operate the furnace if the terminal connectors are red hot. Tighten clamp and/clean contact.
7. Proper grounding guards against shock when working on part of the system. It also prevent damage to sensitive electrical and computer equipment. We recommend ground connections be re-torqued once a year. Electrical ground connection is a MUST.
8. The furnace manufacturer is solely responsible for handling, installation, and control of heating elements, their cycling and furnace heat up time.
9. Maintenance schedules for thermocouples is required for proper control of elements, we recommend they be replaced once a month minimum, depending on the type being used.
10. Procedures mentioned are merely recommendations to follow during installation and are not intended or implied as operating instructions regarding furnace equipment. Refer to furnace manufacturers operation manual.
11. KEEP ELECTRICITY SAFE, always cut power to elements before removing any safety cover. Terminal covers should be tagged DANGER HIGH VOLTAGE.

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