Common Heat Transfer Fluid Problems

• Exposure of Heat Transfer Fluid to air leads to an oxidation reaction that degrades the fluid over time.
• Absence of blanketing with an inert gas (e.g N₂,Ar)

• Increase in viscosity (decrease in heat transfer efficiency)
• Increase in Total Acid Number (TAN). Leads to corrosion problems if moisture is present
• Fouling/Formation of sludge (fouling decreases heat transfer efficiency and increases maintenance costs)
• Fluid discoloration

See our recommendation on Oxidative degradation in the article, ‘Solutions to Heat Transfer Fluid Problems’

• Heating a Heat Transfer Fluid above its bulk temperature results in a cracking of the fluid. A rapid rise in burner/boiler temperature can also crack the fluid.
• Low flow
• Improper burner flame impingement

• Decrease in viscosity, flash point, fire point and autoignition temperature (safety concern)
• Carbon varnishes foul heat transfer surface
• Fluid has pungent/sharp smell

See solution in the article, ‘Solutions to Heat Transfer Fluid Problems’

See our recommendation on thermal cracking in the article, ‘Solutions to Heat Transfer Fluid Problems’

• Pipe/vessel leaks may cause process to enter into the Heat Transfer Fluid causing/accelerating fluid degradation
• Water may get into the expansion tank
• Poor drainage and flushing of degraded Heat Transfer Fluid before replacement with new fluid.

• Rapid fluid degradation
• Corrosion
• Pump cavitation (in a case where water vapor is converted to steam as temperature is increased)
• There could also be adverse effects on fluid viscosity, volatility and heat transfer efficiency

See our recommendations on fluid contamination in the article, ‘Solutions to Heat Transfer Fluid Problems’