If you have a closed-loop plumbing system, which is common in homes with pressure regulators or backflow preventers, a water expansion tank is essential. It’s a small, pressurized tank that absorbs the extra volume created when cold water in your water heater expands as it heats up. Without that tank, pressure builds in the system, which can strain pipes, damage fixtures, and shorten the life of your water heater.
We see this issue often in Bellmore homes where the system doesn’t have anywhere for expanding water to go. Over time, this causes unnecessary wear on your plumbing. A water expansion tank solves that problem by acting like a shock absorber. It relieves stress on your water heater and protects your pipes and fixtures from pressure spikes.
If you’re unsure whether your plumbing system needs an expansion tank, the answer depends on how your system is set up. If your home has a pressure-reducing valve (PRV) or a backflow prevention device, your system is closed. That means it can trap expanding hot water, which puts stress on your entire plumbing system. In those cases, you absolutely need an expansion tank.
Some clues you might notice include frequent relief valve discharges from your water heater, fluctuating water pressure, or even unusual sounds in your plumbing like knocking or banging. These symptoms are usually signs that pressure is building somewhere it shouldn’t. During a routine service or inspection, we can determine whether your system requires an expansion tank and whether one has already been installed and working properly.
Expansion tanks don’t last forever, but they’re a relatively low-maintenance part of your plumbing system. Most models are rated to last anywhere from 5 to 10 years, though lifespan depends on water quality, system pressure, and general usage.
Inside the tank is a rubber bladder or diaphragm that separates the air chamber from the water. Over time, that bladder can wear down, rupture, or lose pressure. When that happens, the tank loses its ability to absorb pressure fluctuations, which defeats the purpose. If you tap the tank and it sounds full instead of hollow, or if you notice water leaking from it, it’s probably time for a replacement.
At World Class Sewer and Drain, we inspect expansion tanks regularly during water heater tune-ups. If it’s starting to fail, we’ll walk you through your options. Replacing one is fast and affordable compared to the damage unchecked water pressure can cause.
Not all expansion tanks are installed correctly. One of the biggest issues we see is tanks that are undersized for the system they’re supporting. If the tank is too small, it can’t handle the thermal expansion, which leads to the same pressure problems you were trying to prevent. Placement also matters. It needs to be installed in the right location on the cold-water line leading into the water heater, and the tank should be pressurized to match your system’s static water pressure.
Another common issue is tanks mounted without proper support. Over time, a full tank puts stress on the plumbing connections, which can lead to leaks or even broken fittings. We always make sure the tank is both the right size and properly secured to avoid future problems.
With professional installation and periodic checks, a water expansion tank can quietly protect your plumbing for years. We’ve helped dozens of customers in Bellmore and surrounding areas solve pressure problems that were quietly damaging their systems behind the scenes.
We uphold the highest standards in the industry, using top-tier tools and techniques to get the job done right. With extensive knowledge and years of experience, we’re ready to handle any sewer or drain crisis, ensuring swift, professional service you can trust.






katherine beavers2025-10-09Trustindex verifies that the original source of the review is Google. Our experience with World Class Sewer and Drain was nothing less than exceptional. They were immensely professional, timely, and knowledgeable. Upon arriving to our flooded basement- they immediately took charge and expertly navigated the situation/identified the cause. Communicating with them about times, $$$ and planning was efficient and effortless. We will absolutely never seek out any other company for our plumbing needs. Thanks guys!!!Posted on Bruce Mapes2025-10-07Trustindex verifies that the original source of the review is Google. I had a bad backup of my kitchen and bathroom sink. I called Mike at World Class and he responded within hours and kept me informed when he was delayed at the prior job. It was a very difficult blockage due to my old galvanized pipes and a T-joint that joined the two. Mike spent almost 2 hours trying to get it unclogged. Most people would have given up, but he persisted and got it cleared. He lived-up to his “world-Class” name. Thanks Mike, I will be calling you again, and recommending you to anyone who asks.Posted on Joy Kim2025-10-06Trustindex verifies that the original source of the review is Google. Amazing service, responds quickly, punctual, and very efficient!Posted on OP2025-09-26Trustindex verifies that the original source of the review is Google. Mike is very professional, highly efficient, and gets the job done. We had a flood emergency at home, and he arrived at our place in about 30 minutes after the phone call. Highly recommend!! Thank you for the wonderful job!Posted on Carol Buchbinder2025-09-23Trustindex verifies that the original source of the review is Google. Excellent, prompt and professional service. Reasonable pricesPosted on David Liebler2025-09-20Trustindex verifies that the original source of the review is Google. Had a major issue with a clogged septic which created backflow and a mess into my basement. Mike and the team came within an hour and fixed everything. Amazing team, and explanation of what happened and what needed to be done to properly to prevent. I would recommend 100% and definitely utilize again as they were honest, reliable and professional.Posted on David K2025-09-12Trustindex verifies that the original source of the review is Google. I had a major issue in my basement with how the plumbing was set up. The previous owner had set up a horrible system. I had three other plumbers look at the issue and all of them misdiagnosed the issue. Mike and Mike recognized it right away and did fantastic work fixing it. Recently, they cleaned out a blockage in my septic tank pipe and replaced a toilet. Throughout the process they walked me through each step of what they were doing. When identifying issues they provided multiple solutions and recommendations. They are extremely professional, always respond quickly, and provide fantastic quality work. I can't recommend them enough.Posted on Richard Levow2025-08-29Trustindex verifies that the original source of the review is Google. On April 19th, 2025 the downstairs toilet in our home overflowed. As a result, the den level and basement required full remediation. This included removing all of the paneling in the den as well as sheetrock in the bathroom and basement. Once the carpeting was removed, we discovered that the floor tile was asbestos which required an additional protocol for removal. Fast forward to August 1st. The space was now roughly 70% done. The downstairs toilet was still not replaced. Someone flushed the upstairs toilet and water came gushing out of the toilet flange downstairs flooding the bathroom, part of the basement and part of the den. That required 4 days worth of work to be ripped out. In addition, I now had another claim with another deductible. As soon as this happened, I called World Class. Mike and Mike came out in the late afternoon and snaked the line from the outside of the house. They strongly recommended that I have them come back and inspect the sewer line with their camera. Mike returned the next week and we discovered that the sewer line to the main was separated. He explained to me that the situation that I had could be repaired with a high tech machine that they use for this type of problem. The machine coats the pipe with an epoxy resin which is more durable than the current pipe material. He assured me that it would resolve the issue. Mike, Mike, Hector and Gio came out that Friday and worked on the sewer line. They were at the house for roughly 10 hours. They worked in a highly professional manner and explained to me what they were doing as they proceeded. Needless to say having your house flood out twice is very stressful. Mike and Mike were excellent at calming my nerves. I highly recommend them should you ever have sewer or plumbing issues.Posted on Annamarie Burriesci2025-08-25Trustindex verifies that the original source of the review is Google. I had World Class Sewer & Drain come to my home in Oceanside, NY to install a new toilet and I couldn’t be happier with the service. The technician showed up on time, was professional, and made the whole process quick and stress-free. The installation was done perfectly and they left the bathroom spotless when they were finished. It’s rare to find a company that takes so much pride in their work and truly cares about their customers. If you need any plumbing work done — big or small — I highly recommend World Class Sewer & Drain. Absolutely five-star service!Posted on Google rating score: 5.0 of 5,
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