The hotter the water the better! However pump cavitation can be a problem at higher temperatures. A hotwell should be correctly designed to mix returning hot condensate with cold 'make up' water. Some hotwells can be too cool, or if a sparge has dropped off the water temperature can be stratified (hot at the top and cooler at the bottom). This means that cooler water is entering the boiler which will require more heat energy to bring the boiler water up to operating temperature. Depending on the amount of condensate returning, steam injectors are used to raise the water temperature in the hotwell, which also means less anti-corrosion chemicals are required.
JBC can carry out hotwell surveys and make recommendations for improvements. New 'bespoke' hotwells are individually designed, manufactured and installed.