Closed Pressurization for Chiller

A closed-loop chiller system is only as reliable as its pressurization. At APT Engineering, we engineer and supply complete closed pressurization units that maintain the precise static pressure every chilled-water circuit requires — preventing air ingress, pump cavitation, and premature equipment failure.

Our pressurization packages are built around expansion automats from Flamco, integrating a diaphragm expansion vessel, a make-up water unit, and a pressure controller into a single compact, factory-tested assembly.

Configuration

Each unit is supplied as a pre-piped, pre-wired package comprising:

• Diaphragm expansion vessel sized to the chiller system volume and operating temperature range
• Automatic make-up water unit with pressure-reducing valve, backflow preventer, and isolation valve
• Pressure controller with adjustable set points for minimum and maximum system pressure
• Safety relief valve, pressure gauge, and drain valve
• Compact stainless steel or powder-coated carbon steel frame for plant-room installation

Benefits / Features

• Maintains precise system pressure automatically — eliminates manual topping-up and the risk of air ingress
• Prevents pump cavitation and bearing damage caused by suction-side pressure drop
• Diaphragm vessel separates system water from pre-charged nitrogen cushion
• Compact skid footprint suits confined plant rooms in high-rise residential and commercial developments
• Factory-assembled and pressure-tested — arrives on site ready for final connection
• Compatible with all major chiller brands and hydronic system designs