Heating coil integrity in the case of using steam as the heating should be monitored by checking the steam condensate returns in the engine room observation tank. If the oil is observed, the source must be traced. An increase in steam consumption should be checked out as this may indicate a steam coil failure. In the case of Heat Oil Storage Tank, oil analysis should be regularly taken and results checked for any HFO contamination. The monitoring of the thermal oil header tank level should also be strictly monitored. Onboard viscosity checks may be useful in determining any thermal oil viscosity change caused by HFO contamination.
The difference of these pressures is the available differential pressure. When the heat exchanger operating pressure is lower than the condensate return pressure, no differential pressure is available and a heat exchanger "stall" may occur. A stall is the reduction or stoppage of condensate flow out of the heat exchanger due to inadequate differential pressure. Thermal Oil Heating System, During stall conditions condensate cannot flow out of the heat exchanger, therefore it backs up or floods the heat transfer surface, which reduces the area available for heating.
The industry has been working with the National Fire Protection Association and Underwriters Laboratory to ensure new tanks are safe and properly installed. The National Fire Protection Association has a comprehensive installation guide for Heat Oil Storage Tank Manufacturers. This includes line protection for the fuel lines, anti-leak devices on the lines, where the tank can be installed, how the fill pipes and vents should be installed, and many other important requirements.