To recharge pressure in a heating water heater, first shut off the power and water supply. Drain 2-3 gallons of water to relieve pressure. Locate the pressure relief valve and lift the lever to release trapped air. If pressure remains below 40-80 PSI, adjust the expansion tank by adding or removing water. Refill the tank, restore power, and test pressure with a gauge.

Maintaining proper pressure in a water heater is critical to prevent inefficiencies and failures. Low pressure causes airlocks, reducing heating efficiency by up to 15% (U.S. Department of Energy, 2022). The expansion tank regulates pressure by absorbing thermal expansion; a 10% capacity loss lowers pressure by 5-8 PSI (Water , 2021). manufacturer guidelines recommend 40-80 PSI to ensure optimal performance. Neglecting pressure recharging can lead to $200-$500 in repair costs annually (Energy Star, 2023). Regular maintenance extends tank lifespan by 6-8 years, saving 20% on energy bills (Journal of Building Engineering, 2020).