4.8G HYDRONIC EXPANSION TANK

ZHT18-30 is a Zilmet Cal-Pro hydronic expansion tank used in residential and light commercial boiler systems.

Product description

Zilmet ZHT18-30 Hydronic Expansion Tank
This model is a ~4.8-gallon diaphragm expansion tank designed to absorb thermal expansion in closed-loop heating systems.

Key specifications

• Type: Hydronic expansion tank (boiler/heating systems)
• Capacity: 4.8 gallons (≈18 liters)
• Connection: 1/2" NPT (some variants 3/4")
• Max pressure: 60 PSI (common rating)
• Max temperature: 210°F
• Precharge: Typically 12 PSI
• Material: Carbon steel tank with internal rubber diaphragm
• Orientation: Vertical or inline installation