The Bell & Gossett Glycol Make-up Unit GF60 (GMU) is an automated 110V diaphragm pump with digital control. Each engineered package is designed to maintain critical minimum pressure levels to make up for losses that may occur due to leakage. The automated system operates as needed to add water or water-glycol solution to a closed loop heating, chilled water, process, snowmelt or radiant heat system. The versatile unit can handle output pressures from 7.5 to 70 psi and has a self-priming pump. In the event of a leak, the system immediately notifies the operator that the fluid level is dropping. The GMU safely shuts off the pump if the storage tank level gets too low, and a pressure relief valve provides protection from excess pressure.