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Internet #202846491

Model #G5L

Store SO SKU #1000837431

2 Gal. Water Heater Expansion/Safety Tank

  • Designed to maintain water pressure and prevent water backflow
  • Polypropylene liner offers a corrosion-resistant water reservoir
  • Handles 150 PSI maximum working pressure at 200°F
  • See More Details

Product Overview

Thermal / hot water heater expansion tanks prevent hot water from back flowing into cold water line or from escaping through the pressure relief valve and onto the floor. Prevents constant fluctuations in water pressure that damage the heater and associated piping. National plumbing code mandates installation when a backflow preventer is present.
  • All U.S. water heater manufacturers require the installation of an expansion tank in closed piping systems
  • Accepts expanded water as system temperature rises due to thermal expansion and returns hot water to system when demand occurs
  • Required by most building codes where backflow preventers are specified
  • Prevents dripping faucets, intermittent toilet fill and pressure relief valve discharge
  • Protects water heater, appliances and fixtures, prevents dangerous pressure buildup
  • Eliminates wasted energy and water, save money and conserve water
  • Deep drawn steel domes for maximum strength and pressure rating
  • Rigid polypropylene liner for corrosion resistant reservoir, butyl diaphragm for long life
  • Welded steel construction welded air charge fitting with protective cap for corrosion resistance and an air-tight seal
  • System connection- 3/4 in. NPTM
  • Maximum operating temperature: 200°F, maximum working pressure: 150 psi, factory pre-charge: 40 psi
  • Sizing - up to a 50 Gal. water heater
  • California residents

Info & Guides

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Warranty / Certifications

Manufacturer Warranty
5 Years

Questions & Answers

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Customer Reviews

  • 4.8
    out of 11 reviews
  • 100% recommend this product
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Showing 1-10 of 11 reviews
We bought a home that had the hot water tank pressure relief valve discharging some water everyda...
We bought a home that had the hot water tank pressure relief valve discharging some water everyday. I discovered it was due to cold water entering the hot water, expanding as it warmed up, and creating excessive pressure. The system lacked a water heater expansion tank. I explored tanks and found I needed at least 4 gallons and this Water Worker tank from Home Depot was reasonably priced and fit the bill. It was easy to adjust the air bladder pressure to match my water pressure and the installation went well. Great product for the price and it solved my problem.
by DillyDilly
  • Verified Purchase
  • Recommended Product
4 Star Review
Rating provided by a verified purchaser
by HomeDepotCustomer
  • Verified Purchase
This was a great addition to my tankless water heater....
This was a great addition to my tankless water heater. Strongly recommend anyone purchasing a tankless add this to your system.
by Tim
  • Verified Purchase
I installed and waiting for winter time ---
I installed and waiting for winter time ---
by Galen
  • Verified Purchase
  • Recommended Product
Pleased with the tank so far
The only quibble I have is that the online instructions describe installing the tank with a saddle valve, but the model I got required a 3/4 inch fitting. I had to get different fittings after I got the unit and saw that it was not as described in the online instructions. Other than that, the tank was easy to install and appears to be good quality. It has solved the problem I had with pressure build-up when water heated up. I am hoping it will have a long lifetime.
by Alabamapete
  • DIY
  • Verified Purchase
  • Recommended Product
100+lbs of pressure down to 40 lbs. USA made and the longest warranty!!
My pressure gauge was pegged at over 100 psi. It blew my water heater. I called my municipal water company and was told that street pressure should be no more than 80 psi. I told them there was something wrong because my meter (inline before my regulator) was reading 100+ psi. They turned it down and my regulator read 80 psi. The next day they turned it back up to 100+ psi. saying people up the hill were complaining of low water pressure and they told me I needed a new regulator. I put in a new regulator and installed a second pressure gauge (with max pressure needle) behind the regulator. Water pressure after the regulator was 40 psi. Good right? Not quite so. Every morning the max capable gauge behind the regulator read 100+ psi. It took me a few days to figure it out. This winter in the northeast has been so cold, the water temp from the main was 35 degrees. Once inside the house, and with the furnaces and water heater running so much, the temperature increase created a large amount of thermal expansion. I installed the unit and my pressure has not risen over 42 psi since. Fantastic! At the same time while everything was off, I also plumbed it so I can easily add a water softener in the future. BONUS! This year for the first time the water line to the refrigerator/ice maker was leaking from the bottom. I thought the pump or something was gone. When I told my wife how good the expansion tank was working, she said maybe high pressure was why the water line to the refrigerator was leaking. Although I didn't think of it, it made perfect sense. Sure enough, I turned the water line back on and no more leaking. That saved me hours looking for the problem and maybe buying a new pump. I think I'll keep both the expansion tank and my wife! Thanks honey :)
by Joseph
  • DIY
  • Verified Purchase
  • Recommended Product
12 people found this helpful
Excellent replacement tank
I purchased this tank to replace an existing tank that had failed. It was very easy to install. Took me all of ten minutes to remove the old tank and install the one. The tank was delivered to my house and was in excellent condition upon receipt.
by Mark2
  • DIY
  • Verified Purchase
  • Recommended Product
Fixed my problems
I would have given this product 5 stars all the way across but finding a saddle valve in the size required is impossible. I used a shark bite T with the right pipe thread to do the install. But as I said, this has fixed my problems with my hot water bleeding out my safety valve and drips at my faucets.
by homeowner
  • DIY
  • Verified Purchase
  • Recommended Product
1 person found this helpful
Godd value for the price.
Good value for the price, cheaper than other vendors.
  • Verified Purchase
  • Recommended Product
Solved the Problem
If you can sweat copper fittings, this is a quick and easy install. Did buy a water gauge to ensure I knew what the max pressure my system was seeing over a day, which cause me to increase the as shipped air pressure in the tank. However, I have not had another drip from my hot water heater relief valve. Only time will tell durability of this tank.
by redrocker
  • Verified Purchase
  • Recommended Product
8 people found this helpful
Showing 1-10 of 11 reviews