Engine 1-4 was alerted to replace units on the initial assignment for a Barn Fire in Antrim Township. Engine 1-4 with a crew of 4 responded immediately. Initial units on scene confirmed a horse barn, well involved. Engine 1-4 arrived and the crew was assigned to relieve initial interior crews looking for remaining fire. Engine 1-4 crew operated for an hour and half before being placed in service by Command 3.