Introducing the NEW Zilmet USA ZEP-1 Stainless Steel Expansion Tank and Shock Arrester for Tankless and POU Water heaters with 2 gallons or less of total water volume.

Most tankless water heater manufacturers require a thermal expansion tank with their water heaters when a backflow preventer is required.  The compact ZEP-1 is the perfect solution for providing thermal expansion protection in tight places.  Stainless steel construction and NSF 61 certified.

Table for pressure v volume for the ZEP1:


Air Pressure (psi)  Volume (mL)
0 173
20 150
40 136
60 91
80 73
100 55
120 18
140 5
150 0