Yes, radiant floor heating systems can also be used for cooling. This is known as radiant cooling or radiant heating and cooling. The system works by circulating cool water or a refrigerant through the tubing or pipes installed beneath the floor surface, which absorbs the heat from the room and transfers it to the cool water or refrigerant. The cooled water or refrigerant is then circulated back to the cooling system to be re-cooled, and the cycle continues. However, it's worth noting that radiant cooling may not be as effective as traditional air conditioning systems in areas with high humidity levels.