Jet fuel and ultra-low-sulfur diesel (ULSD) are produced in a refinery hydrocracker. ULSD and jet fuel are experiencing peak demand because of current market shortages and the effects of the pandemic. Failure to offset any disruption in production would impact revenues dramatically – at a time when demand has never been higher. Aggreko responded rapidly to the challenge when a condenser on a hydrocracker fractionator was taken out of service for maintenance. The refinery was facing a costly decision of downgrading jet fuel and ULSD.