As industrial ovens, dryers and heaters age, questions normally arise about their performance: Are they generating insufficient heat? Are they performing inefficiently? Is there a more cost-effective way to produce more heat? Do I need to replace or refurbish the oven?

Whether ovens are gas or electric, convection or infrared, there are several variables that must be considered before deciding to refurbish or replace your present equipment.

Once an industrial oven goes past its useful life it loses efficiency, which can raise heating costs, delay production or compromise product quality. But before replacing the entire oven with a new unit, users should consider whether refurbishing with an oven retrofit, or upgrading the oven with supplemental heaters, would provide major cost savings and resolve oven underperformance.

“One of the first questions to ask is whether or not the heating requirements have changed,” says Jesse Stricker, founder of Intek Corporation, a Union, Missouri-based manufacturer of heaters and elements for industrial ovens and dryers used in continuous process heating for production automation and material handling in a range of industries.

“It is not unusual for a metalworking company, thermoformer or manufacturer that bakes paint or other coatings onto product surfaces to make changes in processes or materials subjected to heating or curing requirements,” Stricker says. “When such changes occur, it’s quite possible that oven and heater specifications may need to be upgraded.”

More often there are situations where ovens suffer wear and tear from years of use, and the question may be whether to repair or replace the existing system. Stricker recommends that there are a few “conditions” that should be addressed before making that decision:

Condition of current oven: Is it sound mechanically? Ovens usually consist of sheet metal and a structural steel framework. If the structural steel framework and sheet metal is sound, not rusty, perforated or otherwise deteriorated or unstable mechanically, that would indicate that the oven could be refurbished.

Condition of ductwork: If the oven is a convection design, is the ductwork in good condition? If the ductwork is in good condition, not perforated with multiple holes, then it is most likely distributing the heat throughout the oven as designed. This may be handled as part of the sheet metal analysis.

Read more: Resolving Cure Oven Heating Issues