Which Heat Exchanger Is the Most Efficient? A Direct Comparison No single heat exchanger is "the most efficient" in every case. For typical liquid-liquid duties, brazed or gasketed plate heat exchangers reach the highest effectiveness (often 90-95%) because of large, thin heat-transfer surfaces. Shell-and-tube units are less effective per unit volume but remain the most versatile and serviceable for high pressure, high temperature, and fouling services. Efficiency must be