amtrol st-12 expansion tank, therm-x-trol
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amtrol st-12 expansion tank, therm-x-trol in box

Therm-X-Trol ST-12 Thermal Expansion Tank (4.4 Gal Volume)


Brand: Amtrol

Mfr Part#: 141N43

Model: ST-12

UPC#: 642031395672

Availability: In Stock
Usually ships: within 1 business day
Qty Price
$55.50 / each
x4 $217.00 / box
(4 x $54.25)
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  • Description
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Amtrol ST-12 (Therm-X-Trol) is a water heater expansion tank, designed for use in domestic hot water heating systems to eliminate the potential hazards of water expansion.

Water heater expansion tank is commonly installed in a domestic hot water system that contains a backflow preventer, a check valve or a pressure reducing valve.


Amtrol ST-12 Advantages:

Eliminates the waste of energy and water, thus saving money;

Protects the water heater and plumbing fixtures from premauture failure;

Reduces potential safety hazards associated with thermal expansion;

Prevents a dangerous pressure build-up in the system;

Prevents the relief valve from going off;

Therm-X-Trol brand is the #1 choice of Professional Installers;


Amtrol ST-12 Specifications:

Factory pre-charged 40 psig;

System connection: 3/4" male threaded;

Stainless steel system connection;

Max. operating temperature: 200F;

Max. operating pressure: 150 psi;

Expansion tank volume: 4.4 gallons;

Max. acceptance factor: 0.73;

Height: 15";

Diameter: 11";

Shipping weight: 9 lbs;


Standards & Approvals:

NSF/ANSI 61®, IAPMO, SBCCI & City of Los Angeles listings.


Amtrol ST-12 Applications:

Residentail water heaters, laundromats, dormitories, office/apartment buildings, restaurants, etc.

Therm-X-Trol ST-12 Thermal Expansion Tank (4.4 Gal Volume) has an average 5.0 out of 5 rating based on 2 user reviews.
This product came up to my expectations/
By Alex (from Twp. of Washington, NJ) on 11/28/2011
"The order was delivered extremely quickly 2 days after the order was placed. My plumber installed the tank in 5 minutes. The old tank was full of water. I was extremely satisfied !"
reliable product
By mary (from pa) on 8/23/2011
great quality. and they have the best price
Indicate an email address where you wish to receive the answer to your question.
can it be mounted horizontalygs6bk
Read 1 answer
Amtrol allows only for vertical installation of this expansion tank.
Answered on 7/11/2012 by PexUniverse Customer Service

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