The Leading Water Treatment Specialists

Call 1-800-767-8731

Zilmet 2.1 Gallon Inline Stainless Steel Expansion Tank

Model # ZS8
The Z8 STAINLESS STEEL expansion tanks are fit for all applications near coastal areas where the presence of brackishness or harsh chemical environments that rapidly corrode all parts made of plain steel. They allow water expansion in domestic heating systems equipped with boilers or heat exchangers.  They are also used in every application where ultimate hygiene is required, as in a house or a community.
These expansion tanks are equipped with a non-toxic food grade membrane with world wide certifications from demanding organizations for the approval of parts used in the food industry.   Our high quality materials, manufacturing procedures and continuous ZILMET USA quality control, make our INOX PRO tanks a long-lasting life cycle and no need for special maintenance.

Availability: In stock

*Free Shipping‚Äč

Features and Accessories

Product Features

Zilmet is a leading manufacturer and designer of high quality diaphragm well and expansion tanks with over 50 years experience and they have produced over 7.5 million tanks.

Construction Material:

Shell304 Stainless Steel 
Connection304 Stainless Steel 
Fixed MembraneButyl **
** for potable water applications

Operating Conditions:

Maximum Operation Pressure150 PSI
Operationg Temperature210 F
Factory Precharge36 PSI

Additional Info


Additional Info

Model # ZS8
Material Stainless Steel
Capacity 2.1 gallons
Connector 3/4" NPTM
Home Config N/A
drawdown_40_60 .5 gallons
drawdown_30_50 .7 gallons
Shipping Weight 6
Warranty 5 Year Limited


Pressure Tanks

How much air pressure should my pressure tank have?

This depends on which pressure switch you have.  If you have a 40/60 switch, the air pressure in the tank should be set to 38 PSI.  The general rule is to set the pressure at 2 PSI below the cut-in pressure (the pressure at which the pump turns on).
To set this accurately, your well pump must be turned off and all water needs to be drained from the tank.  

What is Drawdown?

Drawdown refers to the amount of water available in a pressure tank for use before the pressure switch turns the pump back on to replenish the supply.  The larger the drawdown, the longer your pump will run for each cycle increasing pump life by reducing the number of times the pump has to turn on. 

Product Literature


Write Your Own Review

You're reviewing: Zilmet 2.1 Gallon Inline Stainless Steel Expansion Tank

How do you rate this product? *

  1 star 2 stars 3 stars 4 stars 5 stars