Yes, he can force a sale of the house through a legal procedure (which is actually a lawsuit) called "partition and sale". This procedure is used when one of the co-owners of real property in California wants to sell, but the other co-owner does not.
In cases where the co-owners cannot agree on the terms of the sale such as the listing agent or initial listing price, the court will appoint a partition referee to carry out the sale. To retain some control, the co-owners could establish parameters which set the bounds of the partition referee’s authority. Absent a consensus, the court simply grants the referee sole discretion and authority regarding the sale. However, any sale will be subject to court approval.
Upon granting judgment partitioning by sale of the property, the court will order that the proceeds of the sale pay the encumbrances thereon, and the net proceeds thereof then be divided between the parties in an equitable amount to be determined by the court, in addition to allowance, accounting, contribution, or other compensatory adjustment among the parties according to principles of equity, pursuant to California Code of Civil Procedure section 872.140. In such a partition action, you will need to present your evidence of why the court ought to distribute the proceeds differently than the ownership percentages.
Note that a partition action does not necessarily mean the property needs to be sold to a third party. One of the co-owners could end up buying out the co-owner(s) and become the sole owner, or alternatively, the court could reallocate the ownership percentages of each co-owner.