Well-designed and properly installed hydronic radiant heating systems have earned a deserved reputation for superior comfort. Even so, many people hesitate on using these systems because they can’t just push a button on their thermostat to change the system from heating to cooling.
All closed-loop hydronic systems require an air space to absorb the increased volume of water as it warms during system operation. In most hydronic systems, this task is handled by an expansion tank. In most modern hydronic systems, it’s handled by a diaphragm-type expansion tank.