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Water heater installers and replacers in O Fallon
When you need fast, reliable plumbing services in the St. Louis area, turn to Mr. Rooter Plumbing of St. Louis. Our local, licensed plumbers provide quality plumbing repairs, maintenance, and drain cleaning services. Call our friendly dispatch team anytime and we'll send one of our uniformed, courteous plumbers to your door ASAP.
"I had 2 emergency toilet shut off valves replaced. Bradley did a great job. He had some extra work to do in 1 of mthe bathrooms. i highly recommend! Tom "
Tom K on May 2025
When you need fast, reliable plumbing services in the St. Louis area, turn to Mr. Rooter Plumbing of St. Louis. Our local, licensed plumbers provide quality plumbing repairs, maintenance, and drain cleaning services. Call our friendly dispatch team anytime and we'll send one of our uniformed, courteous plumbers to your door ASAP.
"I had 2 emergency toilet shut off valves replaced. Bradley did a great job. He had some extra work to do in 1 of mthe bathrooms. i highly recommend! Tom "
Tom K on May 2025
When you need fast, reliable plumbing services in the St. Charles County area, turn to Mr. Rooter Plumbing of St. Charles. Our local, licensed plumbers provide quality plumbing repairs, maintenance, and drain cleaning services, all backed by our Done Right Promise. Call our friendly dispatch team anytime and we'll send one of our uniformed, courteous plumbers to your door ASAP.
"Mr. Rooter provided great, and speedy, service!!"
Reginald J on October 2024
When you need fast, reliable plumbing services in the St. Charles County area, turn to Mr. Rooter Plumbing of St. Charles. Our local, licensed plumbers provide quality plumbing repairs, maintenance, and drain cleaning services, all backed by our Done Right Promise. Call our friendly dispatch team anytime and we'll send one of our uniformed, courteous plumbers to your door ASAP.
"Mr. Rooter provided great, and speedy, service!!"
Reginald J on October 2024
We take great pride in our experience, expertise, quality and customer service, that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship, and complete customer satisfaction, from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate, with every customer in a professional manner. Our reputation is based on service, safety and quality, regardless of how large, or small the job. Call us today!
"Kris, worked solo for almost 8 hrs to get the job done with help only the last hr or so. All after suffering a medical emergency. He wanted to come the day after but, I insisted not to come until he was better which only caused a delay of one day. He went above and beyond to remove obstacles in his way to get my hot water tank installed. Also, he cleaned up and removed all trash and even mopped the basement floor. Needless to say I’m very happy with the service provided."
K H on June 2025
We take great pride in our experience, expertise, quality and customer service, that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship, and complete customer satisfaction, from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate, with every customer in a professional manner. Our reputation is based on service, safety and quality, regardless of how large, or small the job. Call us today!
"Kris, worked solo for almost 8 hrs to get the job done with help only the last hr or so. All after suffering a medical emergency. He wanted to come the day after but, I insisted not to come until he was better which only caused a delay of one day. He went above and beyond to remove obstacles in his way to get my hot water tank installed. Also, he cleaned up and removed all trash and even mopped the basement floor. Needless to say I’m very happy with the service provided."
K H on June 2025
We take pride in our company's reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!
"My hot water heater went out. I called several plumbers and was being quoted astronomical amounts along with quite a wait time to get to me. Brice was able to get the job done quickly (since no hot water sucks) and at a price I could live with. He was super funny and professional and made me feel like a friend had come over to help. I will always call him first for any of my plumbing needs "
penny a on June 2025
We take pride in our company's reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!
"My hot water heater went out. I called several plumbers and was being quoted astronomical amounts along with quite a wait time to get to me. Brice was able to get the job done quickly (since no hot water sucks) and at a price I could live with. He was super funny and professional and made me feel like a friend had come over to help. I will always call him first for any of my plumbing needs "
penny a on June 2025
We pride ourselves on our extreme professionalism and attention to detail. Our customer satisfaction guarantee will assure you we will not leave your property until you are completely satisfied with our work. As a locally owned and operated business you can trust that we will treat your home as we would treat our own. Give us a call today, and we look forward to working with you!
"Got it done quick and clean. "
rita n on June 2025
We pride ourselves on our extreme professionalism and attention to detail. Our customer satisfaction guarantee will assure you we will not leave your property until you are completely satisfied with our work. As a locally owned and operated business you can trust that we will treat your home as we would treat our own. Give us a call today, and we look forward to working with you!
"Got it done quick and clean. "
rita n on June 2025
At Thomas Hoffmann Air Conditioning and Heating, it is our privilege to partner with you to provide quality service each time you call. We aim to exceed your expectations through our responsiveness, integrity, and expertise. Our team of experienced technicians is dedicated to providing top-quality heating, cooling, and ventilation services for homes and businesses throughout the area. From routine maintenance and repairs to complete system installations, we have the skills and knowledge to keep your indoor environment comfortable all year round.
"Great job with a service of my furnace and HVAC. Good value for money. highly recommended."
Andrew C on July 2024
At Thomas Hoffmann Air Conditioning and Heating, it is our privilege to partner with you to provide quality service each time you call. We aim to exceed your expectations through our responsiveness, integrity, and expertise. Our team of experienced technicians is dedicated to providing top-quality heating, cooling, and ventilation services for homes and businesses throughout the area. From routine maintenance and repairs to complete system installations, we have the skills and knowledge to keep your indoor environment comfortable all year round.
"Great job with a service of my furnace and HVAC. Good value for money. highly recommended."
Andrew C on July 2024
We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!.
"He was prompt and efficient but did not show up on time."
CINDA A on February 2025
We pride our company on reliability, great communication, integrity, and quality work. We are experts in our trade and will do our best to keep you as educated as we can on your particular task or project. We look forward to earning your business!.
"He was prompt and efficient but did not show up on time."
CINDA A on February 2025
We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.
"Both the estimator Kevin the two installers who visited my home were very professional and kind. They answered all my questions and provided a very reasonable price for the installation of the attic insulation. I feel I was very informed on the federal rebate that was available for this installation, as well as on the recommendations of quantity of insulation I needed per residential standards and codes. I would recommend Anton and will use them in the future for my HVAC needs!"
Haley D on November 2024
We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumer's needs. It is our mission to provide excellent workmanship and complete customer satisfaction from start to completion of a project. In order to understand the needs and expectations of our customers, we take great care to work and communicate with every customer in a professional manner. Our reputation is based on service, safety, and quality, regardless of how large or small the job.
"Both the estimator Kevin the two installers who visited my home were very professional and kind. They answered all my questions and provided a very reasonable price for the installation of the attic insulation. I feel I was very informed on the federal rebate that was available for this installation, as well as on the recommendations of quantity of insulation I needed per residential standards and codes. I would recommend Anton and will use them in the future for my HVAC needs!"
Haley D on November 2024
Family owned and operated, we perform. With over 20 years of experience we know what it takes to make you happy. We are local in Chesterfield and our top priority is a satisfied customer.
"I had a horrible experience with Maris Home Improvements. I don't recommend them. You are better off going with Window World!"
Monica C on May 2025
Family owned and operated, we perform. With over 20 years of experience we know what it takes to make you happy. We are local in Chesterfield and our top priority is a satisfied customer.
"I had a horrible experience with Maris Home Improvements. I don't recommend them. You are better off going with Window World!"
Monica C on May 2025
At Premier 1 Properties, LLC, we solve all of your design, installation, and remodel concerns on custom home remodeling projects.The services that we are known for include Complete basement finishes, flooring work, kitchen remodeling, and bathroom remodeling/renovation in St. Charles County and St Louis County, Missouri. Our other services include: general contracting, full house remodel and restoration, and purchasing old homes for renovation, Providing quality work for our clientele is always our main priority. We service all of St. Charles and West St. Louis County, MO. For more information on the services we provide, contact us today.
"The team was great! The team members made a great effort to get things done in a timely manor & as coast effectively as possible. A few times they called & came in on weekends to get some things done too. They worked around our schedule too. Rick & some of the other team members helped with decisions on colors & material. They went above & beyond the work they were hired to do to help me. Made sure everything was perfect. Was nice enough to even put plywood over the counters till they could get the cabinet top in. This way we were able to use our kitchen. There was a cracked/broken toilet tank lid. Rick took it back & exchanged it & brought out a new one. Rick & the team picked out the stove & hood to match along with the dishwasher. So I didn’t have to any thing They even scheduled delivery from stores so they were here to except & inspect for faults Very conscious of the dogs & not letting them out & working around them at times."
Phyllis M on October 2019
At Premier 1 Properties, LLC, we solve all of your design, installation, and remodel concerns on custom home remodeling projects.The services that we are known for include Complete basement finishes, flooring work, kitchen remodeling, and bathroom remodeling/renovation in St. Charles County and St Louis County, Missouri. Our other services include: general contracting, full house remodel and restoration, and purchasing old homes for renovation, Providing quality work for our clientele is always our main priority. We service all of St. Charles and West St. Louis County, MO. For more information on the services we provide, contact us today.
"The team was great! The team members made a great effort to get things done in a timely manor & as coast effectively as possible. A few times they called & came in on weekends to get some things done too. They worked around our schedule too. Rick & some of the other team members helped with decisions on colors & material. They went above & beyond the work they were hired to do to help me. Made sure everything was perfect. Was nice enough to even put plywood over the counters till they could get the cabinet top in. This way we were able to use our kitchen. There was a cracked/broken toilet tank lid. Rick took it back & exchanged it & brought out a new one. Rick & the team picked out the stove & hood to match along with the dishwasher. So I didn’t have to any thing They even scheduled delivery from stores so they were here to except & inspect for faults Very conscious of the dogs & not letting them out & working around them at times."
Phyllis M on October 2019
FAQs for water heater installation and replacement projects in O Fallon, MO
You'll need an expansion tank if your home has a closed water system, which is standard in newer homes or those with backflow preventers or pressure regulators. Expanding hot water has nowhere to go in closed systems, creating potentially damaging pressure. The expansion tank provides space for this expanded water, protecting your plumbing system and water heater from premature failure. Many local building codes now require expansion tanks, and some water heater warranties may be voided without one.
For a standard 50-gallon water heater, a two-gallon expansion tank is sufficient. This sizing assumes normal household water pressure between 40 and 60 psi. If your home has higher water pressure (60 to 80 psi), consider upgrading to a slightly larger tank for added protection. The expansion tank's purpose is to accommodate the increased volume that occurs when cold water heats up, which is proportional to your water heater's capacity.
Watch for signs like dripping water around the tank, fluctuating water pressure throughout your home, or unusual noises in your plumbing system. A properly functioning expansion tank should feel light when tapped on the bottom—if it feels heavy or waterlogged, the internal bladder has likely failed. Other indicators include frequent triggering of your temperature and pressure relief valve, visible corrosion on the tank, or unexplained increases in your water bill, suggesting hidden leaks.
Most expansion tanks have a service life of five to 10 years, though some may last up to 12 years or more with proper maintenance. Factors affecting lifespan include water quality, system pressure, installation quality, and tank construction. Hard water areas often see shorter lifespans due to mineral buildup. Regular maintenance checks can help identify potential issues before complete failure. When your water heater is due for replacement, it's wise to replace the expansion tank simultaneously, even if it hasn't failed yet.
A 30-gallon water heater needs an expansion tank if your home has a closed plumbing system. The need for an expansion tank is determined by your plumbing system type rather than water heater size. Even smaller water heaters create thermal expansion when heating water. If your home has a backflow preventer, pressure regulator, or check valve on the main water line, you have a closed system that requires an expansion tank. Check your local plumbing codes, as many jurisdictions now mandate expansion tanks regardless of water heater size.
- Plumbing - Multiple Projects
- Shower Pan Install
- Plumbing for a Remodel or Addition - Install
- Plumbing Item Repair
- Water Heater - Repair or Service
- Sink Repair
- Steam Shower - Install
- Faucet Install or Replace
- Walk In Tub - Install or Replace
- Drain Repair
- Shower Install or Replace
- Pipe Repair
- Drain Line Breakage - Camera Locate
- Tankless Water Heater - Install
- Water Main - Install, Replace or Repair
- Sump Pump - Repair or Replace
- Drain Clog or Blockage - Clear
- Sewer Main - Clear
- Faucets, Fixtures and Pipes - Repair or Replace
- Plumbing Item Installation
- Sink Installation
- Pipe Installation
- Faucet Installation
- Gas Piping
- Whirlpool Bathtub Install or Replace
- Plumbing Multi-Item Installation
- Sewer Main - Install, Replace or Repair
- Drain Installation
- Plumbing Multi-item Repair
- Toilet Installation
- Bathtub Install or Replace
- Sump Pump or Interior Foundation Drains - Install
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