Grundfos CR Series pumps feature a cast iron top and base with AISI 304 stainless steel wetted parts. ... Grundfos Dosing Pumps. Hot Water Recirculation Pump. Dosing Pump Parts/ Accessories. Dosing Tank Stations. Have questions? Get help 24 hours a day, 7 days a week. Click "Contact Us" in the navigation bar at the top of any page.