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$65.07 each
In Stock
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MANUALS (5)
This item replaces: 91121984
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Product Highlights
–
2 Gallons
3/4" Connection
7 Year Warranty
150 MAX PSI
Threaded Connection
8" Diameter
Description
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Amtrol ST-5 (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.
The HydroClaw Expansion Tank Support Bracket provides a safe and reliable option if you prefer to mount your expansion tank. This expansion tank bracket is easy to install and will hold any tank with a diameter of 8" nominal.
Amtrol ST-5 Advantages:
The HydroClaw Expansion Tank Support Bracket provides a safe and reliable option if you prefer to mount your expansion tank. This expansion tank bracket is easy to install and will hold any tank with a diameter of 8" nominal.
Amtrol ST-5 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
Specs
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| Connection Size: | 3/4" |
|---|---|
| Warranty: | 7 Year |
| Connection Type: | Threaded |
| Tank Volume: | 2 Gallons |
| Max Accept. Factor: | 0.45 |
| Diameter (Inches): | 8" |
| Height: | 12-5/6" |
| Material: | Steel |
| Application: | Plumbing |
| Max Pressure (PSI): | 150 |
| Weight (lbs): | 5 lbs |
| Temperature Range (F): | 200°F MAX |
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Product Reviews
4.81 out of 109 reviews
96% would recommend this product
5 star
91%
4 star
5%
3 star
2%
2 star
0%
1 star
3%
Customer Images
Most Liked Positive Review
Works as advertised, good quality
As I understand, this is the version of the Amtrol 2-gallon tank that is made in the US. The quality seems good and I had no problems with it. My new water heater used to leak from the pressure relief valve, now it doesn't. I mounted it horizontally. There are brief instructions. What they don't tell you anywhere is that the plumbing connection is 3/4" male pipe thread. I reduced that to 1/2" and then used a 1/2" pex adapter.
I used a floor-type bicycle pump to pressurized to my water pressure (80 psi). It's a little difficult when the pump is upside down, but doable.
VS
Most Liked Negative Review
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nipple thread size needs better QC
Therm-X-Trol is the best residential expansion tank, but there has been an ongoing issue with the thread size of the 3/4 SS nipple. with 7 or so threads available, 1 to 1-1/2 turns of the fitting, finger tight dry is unacceptable. 2 turns barely passes, because with 3 wraps of teflon tape, the number of turns is even less. 4 to 5 turns dry finger tight would leave 3 turns with sealant applied, a better fit to prevent leaks.
had to return/replace a couple of recent units due to poor thread size QC.
one must ask: if one can only use 1 or 1-1/2 turns of thread engagement, what are the other 5 turns there for? they are there to provide an adequate leak-free seal, so please cut those threads a bit deeper so we can use enough of them.
because every other aspect of this product is wonderful, I will be glad to rate 5 stars and recommend to others when the nipple thread size is fixed.
Showing 1-10 of 109 reviews
Failed in less than 2 years
I bought this brand because the previous ThermXtrol had lasted over 15 years, which is incredible. But this one lasted only 22 months. It was the exact same size, I pressurized it to match my house's water pressure, and checked that pressure once about a year ago. My only doubt is the orientation - the install instructions say to mount it with the Schrader valve on the bottom, but I can't bc the supply line it's on is too close to the floor. But the plumbers on Reddit say orientation doesn't matter, so who knows. The old one was mounted the exact same way and lasted forever, so I think this one is just junk.
BleatingGoat
Denver, CO
25 days ago
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Great product, Fast shipping
Came in one day, no fees, the perfect fit!
Hamr4u
Pennsylvania
3 months ago
Verified Buyer
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Great product, Fast shipping
My local distributor didn't carry this expansion tank, used my online SupplyHouse account and it was actually less! I receive free shipping being a TradeMaster plus received it in one day!
Hamr4u
PA
4 months ago
Verified Buyer
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Second one, lasted 7 years
I'm a plumber since 1976, retired now. I have never had a callback for this tank. I had to replace the extrol tank on the city water piping next to my water heater. The old one lasted about 8 years. Worked perfectly and keeps the house pressure around 50 pounds.
Retired
NJ
6 months ago
Verified Buyer
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Excellent Service and Quality Products
Supply House always has what I need. Every time I order I get products sooner than estimated. Outstanding Service!
Geraldo
New Mexico
7 months ago
Verified Buyer
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As depicted. Good Quality
Good quality product recommended by my Geo Thermal installation company.
Joe L.
Fairfax Station
8 months ago
Verified Buyer
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Solved our thermal expansion problem
We have a Noritz NRCR111 which required an expansion tank on the hot recirculating return line because of thermal expansion issues. We installed the ST-1 which didn't help; then installed the ST-5 solved the problem.
Sam
San Diego, CA
9 months ago
Verified Buyer
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great product
We switched back to Amtrol expansion tanks once our wholesalers' competitive brands started experiencing deterioration of the interior bladder and would completely fill with water as soon as 3 years from initial installation. This was not an air loss but a bladder loss. We pay slightly more for the Amtrol but they hold up.
NIck
Bay Area, California
12 months ago
Verified Buyer
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Great company, experience-as usual
Very happy with the speed of delivery and the customer service staff. Have and will continue to use these guys going forward!
Bob D.
Woodbury, CT
1 years ago
Verified Buyer
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Tank works perfectly.
Incoming pressure is 70 psi. I set the tank bladder to 70 psi. No more water coming out of the pressure relief valve on the hot water tank after using alot of hot water. Works great!
SteelCity
Pittsburgh, Pa
1 years ago
Verified Buyer
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Product Q&A
10 Questions10 Questions
Q: Can this be filled to 90psi to match incoming water pressure?
Asked by Jordan 2 years ago
Add your answer
Verified Reply- SupplyHouse StaffHi Jordan, thanks for writing in. This expansion tank has a max working pressure of 150 PSIG (10.3 bar).
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Q: Is the male thread connection 1/2" or 3/4"
Asked by Joshua 10 years ago
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3/4 Sent from my iPhone Ryan C.
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Q: Does this expansion tank require any maintenance?
Asked by KC Water Heaters 11 years ago
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The only maintenance I performed was to ensure it had the correct PSI before I installed it.
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- Smitty
Hi, Not to my knowledge. I installed it in my hot water heating system and that was that. It has an internal bladder that expands as the hot water enters it and keeps the pressure valve from opening. When it goes bad and the bladder developes a hole the pressure valve will start to open when the heater comes on and heats the water in the system.
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Q: Is this tank for use with potable water systems?
Asked by Cloves 11 years ago
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YES!
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Q: I am getting temp fluctuations with a new boiler equipped with instant hot water. I already have a pressure reducing valve. would this improve the temp fluctuations?
Asked by Paul 12 years ago
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I don't believe it well help with temperature. The tank is for helping to even pressure out and avoid pressure drops during usage.
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Q: what gallon size?
Asked by greg 12 years ago
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Verified Reply- Supplyhouse Staffthat one is 2 gallon
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Q: does it matter what position the unit is mounted? horizontal vertical etc.
Asked by grump 15 years ago
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Verified Reply- PexSupply StaffNo, the expansion tank can be mounted in any orientation.
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- corky meier handyman service.
no, you can mount sideways or upside down. it is a bladder tank so it will be ok any position.corky
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- Plumbsmart
The installation instructions say to "install in the downward position only"
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Q: will this model work on 30 gal residential heater?
Asked by Dave 15 years ago
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Verified Reply- PexSupply StaffYes, it will.
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Q: This tank has a male SS connection. Can it be directly threaded to a female copper connection or is a dielectric connection required to prevent any corrosion long term from electrolysis.
Asked by dbrostrain 15 years ago
Add your answer
Verified Reply- PexSupply StaffAccording to the manufacturer, you will not need a dielectric union and you will not get any long-term electrolysis.
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Q: how to install replacement?
Asked by Bob 15 years ago
Add your answer
Verified Reply- PexSupply StaffPlease view the following installation manual for detailed instructions: http://s3.pexsupply.com/manuals/1260456120583/20366_PROD_FILE.pdf
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