§ 249. Transfer of appropriations. All appropriations or reappropriations for the functions herein transferred heretofore made to the public service commission or the department of public service, or segregated pursuant to law, to the extent of remaining unexpended or unencumbered balances thereof, whether allocated or unallocated or whether obligated or unobligated, are hereby transferred to and made available for use and expenditure by the department for the same purposes for which originally appropriated or reappropriated and shall be payable on vouchers certified or approved by the commissioner on audit or warrant of the comptroller. Payments for liabilities for expenses of personal service, maintenance and operation heretofore incurred by the public service commission or the department of public service in connection with the functions herein transferred, and for liabilities incurred and to be incurred in completing their affairs in relation to the functions transferred herein, shall also be made on vouchers or certificates approved by the commissioner on audit and warrant of the comptroller.