The single cointegration vector model used for condition monitoring does not have uniform power for every faulty condition according to previous research work on a hydraulic flap servo system, and thereis lack of explanation for t he multi cointegration relations from the view of condition monitoring. To addre ss this problem, a new explanation between condition monitoring and space is given based on the existing cointegration relations. Thereby, a new linear combina tion model of multi cointegration vectors is proposed to improve the performance of the single cointegration vector model. The comparative study confirms that the new approach has better monitoring power.