Temperature control has a great deal to do with the life of your heater. There are many different types of temperature control on the market today. It will be impossible to cover all of them, so this article will cover the benefits, as they would affect heater life.

(1) Soft start is used to dissipate the moisture that has gathered in the heater because of humidity and other contamination in the environment. If this contamination is not removed before the heater reaches 212xF, the moisture may turn to steam and dissipate some of the Magnesium Oxide Powder (M.G.O.) as the steam exits the heater.

After all the M.G.O. is dissipated from any area of the heater, the heater coil can touch the sheath and short out. This will cause the heater to go to ground and the sheath to arc-weld itself to the inside of the heater hole.

(2) A voltage-proportioning, phase angle-fired type of controller eliminates the thermo shock created by an on-off type controller. The voltage proportioning type of controller provides only the amount of voltage required to maintain set point. An on-and-off type of controller provides full-rated voltage to the heater until it reaches set point and then no voltage until the heater calls for heat.

During this on/off cycle, temperature swings can be very great – causing product quality problems, which also could cause premature heater failure because of expansion and contraction of the thread-like heater element.

(3) The ground fault detecting system detects excessive moisture or other resistance to ground and prevents the control from applying high voltage until the heater is dry or the resistance to ground has been eliminated.

It is very important that moisture be dissipated from the heater before full-rated voltage is applied. If a soft start-type of control system is not available, you can dry your heaters by using manual mode at 10 to 15 percent for about 20 minutes. This should add considerable life to your heaters. When it comes time to replace your existing control system, compare and purchase the best you can afford. It will save you many hours of downtime due to heater failure.