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Tankless water heater installers in Alton

Avatar for Cardinal Plumbing
Cardinal Plumbing
3133 Washington Ave
5.00(
3
)
Approved Pro
Cardinal Plumbing
3133 Washington Ave
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
57 local quotes requested

Voted BEST Plumbing Company in Madison County by the readers of The Telegraph and Riverbend Association. 🏆 Cardinal Plumbing is a Premiere Plumbing outfitter for all residential and commercial service remodels, excavation, water service, interior plumbing and more! We are famous for our 5-Star rating and A+ with the Better Business Bureau offering YOU Service With Excellence. ✅ 24 Hour Emergency Service Available❗️ 📲(618) 215-3780

"."

Kathy R on March 2025

Voted BEST Plumbing Company in Madison County by the readers of The Telegraph and Riverbend Association. 🏆 Cardinal Plumbing is a Premiere Plumbing outfitter for all residential and commercial service remodels, excavation, water service, interior plumbing and more! We are famous for our 5-Star rating and A+ with the Better Business Bureau offering YOU Service With Excellence. ✅ 24 Hour Emergency Service Available❗️ 📲(618) 215-3780

"."

Kathy R on March 2025


Avatar for Tiger Plumbing, Heating, Air Conditioning, & Electrical Services
Tiger Plumbing, Heating, Air Conditioning, & Electrical Services
1902 Vandalia Street, Suite 100
3.78(
79
)
Approved Pro
Tiger Plumbing, Heating, Air Conditioning, & Electrical Services
1902 Vandalia Street, Suite 100
3.78(
79
)
Approved Pro
Customers say: Quick response
1863 local quotes requested
32 years of experience

Tiger Plumbing, Heating, Air Conditioning, & Electrical Services takes pride in being your preferred local plumbers, electricians, and HVAC technicians! In fact, more homeowners in the St. Louis Metro East & Central Illinois communities we serve, say they would call us again before any other plumbing, electrical, heating, or air conditioning service!

"My technician Keith was great. Friendly and super informative. Also too a quick look at the entire drainage system and gave my an idea of where problems will pop up the future without preventative measures (my home was built in the 50s and while the previous owners took really good care of the house nothing has been gutted and replaced yet)."

Amber N on January 2025

Tiger Plumbing, Heating, Air Conditioning, & Electrical Services takes pride in being your preferred local plumbers, electricians, and HVAC technicians! In fact, more homeowners in the St. Louis Metro East & Central Illinois communities we serve, say they would call us again before any other plumbing, electrical, heating, or air conditioning service!

"My technician Keith was great. Friendly and super informative. Also too a quick look at the entire drainage system and gave my an idea of where problems will pop up the future without preventative measures (my home was built in the 50s and while the previous owners took really good care of the house nothing has been gutted and replaced yet)."

Amber N on January 2025


Avatar for Roto-Rooter Plumbing & Water Cleanup
Roto-Rooter Plumbing & Water Cleanup
4806 Trade Access Blvd
4.48(
960
)
Approved Pro
Roto-Rooter Plumbing & Water Cleanup
4806 Trade Access Blvd
4.48(
960
)
Approved Pro
Customers say: Super punctual
2239 local quotes requested
90 years of experience

When you need an emergency plumber or a drain cleaner, call Roto-Rooter Plumbing & Water Cleanup. Your fast & reliable plumber can fix any plumbing problem, including sump pumps, toilet repair, faucet repair, faucet replacement, garbage disposals, water heaters, bathtubs, showers, and outside faucets. Roto-Rooter is best known for drain cleaning & sewer cleaning. We fix drain clogs, clogged toilets or sinks, blockage of main sewer lines, slow draining shower and bathtub drains, sewer lines and leaking or burst pipes. We also specialize in water damage restoration & water cleanup services. We can fix and clean up your flooded basement too. Roto-Rooter is a 24-hour plumber near you and provides emergency service.

"Very professional service, and great customer service."

Janet H on April 2025

When you need an emergency plumber or a drain cleaner, call Roto-Rooter Plumbing & Water Cleanup. Your fast & reliable plumber can fix any plumbing problem, including sump pumps, toilet repair, faucet repair, faucet replacement, garbage disposals, water heaters, bathtubs, showers, and outside faucets. Roto-Rooter is best known for drain cleaning & sewer cleaning. We fix drain clogs, clogged toilets or sinks, blockage of main sewer lines, slow draining shower and bathtub drains, sewer lines and leaking or burst pipes. We also specialize in water damage restoration & water cleanup services. We can fix and clean up your flooded basement too. Roto-Rooter is a 24-hour plumber near you and provides emergency service.

"Very professional service, and great customer service."

Janet H on April 2025


Avatar for Perfect Choice Home Solutions Your Authorized Bath Planet Dealer of St. Louis
Perfect Choice Home Solutions Your Authorized Bath Planet Dealer of St. Louis
2424 MO-94 South Outer Rd
4.81(
127
)
Approved Pro
Perfect Choice Home Solutions Your Authorized Bath Planet Dealer of St. Louis
2424 MO-94 South Outer Rd
4.81(
127
)
Approved Pro
Customers say: Terrific value
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
5197 local quotes requested

Complete Bath and 2 Day Remodeling services offered: also roofing, siding, windows, and gutter/gutter cover installations. Bath Planet has been the go-to St. Louis bathroom remodeling company for over 17 years. From replacement shower surrounds to bathtubs that are designed to fit perfectly over your existing tub, our experienced team has what it takes to provide you with a bathroom that is beautiful and extremely easy to maintain. Not only do we believe very strongly in providing quality, long-lasting products, we also believe in providing an outstanding customer experience. We offer free estimates, and we can complete your project in as little as one day. We also have energy Star double pane windows, beautiful vinyl siding looks like real wood, roofing of all different styles.

"Bath Planet's customer service team went above and beyond to ensure our satisfaction. They were friendly, knowledgeable, and always available to answer our questions. We are very pleased with our new shower!"

Aleksandr B on May 2024

Complete Bath and 2 Day Remodeling services offered: also roofing, siding, windows, and gutter/gutter cover installations. Bath Planet has been the go-to St. Louis bathroom remodeling company for over 17 years. From replacement shower surrounds to bathtubs that are designed to fit perfectly over your existing tub, our experienced team has what it takes to provide you with a bathroom that is beautiful and extremely easy to maintain. Not only do we believe very strongly in providing quality, long-lasting products, we also believe in providing an outstanding customer experience. We offer free estimates, and we can complete your project in as little as one day. We also have energy Star double pane windows, beautiful vinyl siding looks like real wood, roofing of all different styles.

"Bath Planet's customer service team went above and beyond to ensure our satisfaction. They were friendly, knowledgeable, and always available to answer our questions. We are very pleased with our new shower!"

Aleksandr B on May 2024


Le Roy Construction & Remodeling
707 N Illinois St
4.75(
4
)
Approved Pro
Le Roy Construction & Remodeling
707 N Illinois St
4.75(
4
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
687 local quotes requested

We specialize in all phases of remodeling for your home, business, bathrooms, kitchens, finishing basements, and more! We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service! Check out all the services we offer below and call -or- click to schedule a free estimate today!

"Everything went great. Job completed on time and clear communication and expectations throughout."

John k on August 2021

We specialize in all phases of remodeling for your home, business, bathrooms, kitchens, finishing basements, and more! We guarantee your satisfaction, and we won’t leave until the job is done right. We pride ourselves on the quality work we provide, while delivering great customer service! Check out all the services we offer below and call -or- click to schedule a free estimate today!

"Everything went great. Job completed on time and clear communication and expectations throughout."

John k on August 2021


Avatar for Neli Virtual Appliance Repair
Neli Virtual Appliance Repair
143 Charlotte Ave
4.29(
572
)
Approved Pro
Neli Virtual Appliance Repair
143 Charlotte Ave
4.29(
572
)
Approved Pro
Customers say: Super punctual
50627 local quotes requested
9 years of experience

Virtually diagnose and/or repair your appliances and HVAC units today without anyone stepping foot inside your home! Starting at $40 you can take control of your home appliance repairs via video chat with a certified technician when it’s convenient for you. Make an appointment today on our website. Neli's certified technicians will work with you to conduct either a diagnosis to find out what's wrong or a repair. You will use Neli’s advanced video chat technology during your appointment. Schedule your appointment today at nelihome.com or call us at 833-876-0900!

"This was amazing! I had no idea this service existed. After searching and contacting various repair places for my washer, this was the most cost effective option. I figured if it didn't work, my machine is old and I would be out $40, not the $100+ to have a tech come out and just diagnose the problem. I am pretty handy and my washer is old anyway, so if it is broken, I have to get a new one anyway. My tech, Steve, was great! He predicted what was wrong after listening to the machine, calmly walked me through dismantling the machine and when we got down to the motor, he was right! He sent me a link to the part I would need, and let me know to contact them again if I needed help installing it. My machine works even better than before it broke, its beautifully quiet and efficient. I will definitely be saving this company for any future repairs on appliances I may need. The service was $40 + the part cost, which was about $8."

Jennifer S on March 2025

Virtually diagnose and/or repair your appliances and HVAC units today without anyone stepping foot inside your home! Starting at $40 you can take control of your home appliance repairs via video chat with a certified technician when it’s convenient for you. Make an appointment today on our website. Neli's certified technicians will work with you to conduct either a diagnosis to find out what's wrong or a repair. You will use Neli’s advanced video chat technology during your appointment. Schedule your appointment today at nelihome.com or call us at 833-876-0900!

"This was amazing! I had no idea this service existed. After searching and contacting various repair places for my washer, this was the most cost effective option. I figured if it didn't work, my machine is old and I would be out $40, not the $100+ to have a tech come out and just diagnose the problem. I am pretty handy and my washer is old anyway, so if it is broken, I have to get a new one anyway. My tech, Steve, was great! He predicted what was wrong after listening to the machine, calmly walked me through dismantling the machine and when we got down to the motor, he was right! He sent me a link to the part I would need, and let me know to contact them again if I needed help installing it. My machine works even better than before it broke, its beautifully quiet and efficient. I will definitely be saving this company for any future repairs on appliances I may need. The service was $40 + the part cost, which was about $8."

Jennifer S on March 2025


MISSOURI VALLEY RENEWABLE ENERGY
2378 BERKEMEYER RD
No reviews
MISSOURI VALLEY RENEWABLE ENERGY
2378 BERKEMEYER RD
No reviews
23 years of experience

Marin Construction
414 Bismark Ave
No reviews
Marin Construction
414 Bismark Ave
No reviews
17 years of experience

general remodeling

general remodeling


Custom Remodel
1130 Hollywood Hts
4.93(
15
)
Custom Remodel
1130 Hollywood Hts
4.93(
15
)
Customers say: Quality work
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers

Custom Remodel has spent the last 20 years specializing in designing custom cabinets. We will design, build and install your cabinets. We can create entertainment centers, mantels, kitchen islands, bars, closet organizers,custom cabinet doors and most woodworking projects. We are with you from start to finish to make sure that your vision becomes a reality. We are licensed and insured. We offer top-notch skilled craftsmanship and take special care to finish details. See more photos on our Facebook Page, Customremodel.

Custom Remodel has spent the last 20 years specializing in designing custom cabinets. We will design, build and install your cabinets. We can create entertainment centers, mantels, kitchen islands, bars, closet organizers,custom cabinet doors and most woodworking projects. We are with you from start to finish to make sure that your vision becomes a reality. We are licensed and insured. We offer top-notch skilled craftsmanship and take special care to finish details. See more photos on our Facebook Page, Customremodel.


A&B Home Improvement
3514 Oscar Ave
No reviews
A&B Home Improvement
3514 Oscar Ave
No reviews

We take care of all your Home Remodeling and Repair needs, big or small. We offer drywall services, plastering, painting. We build, repair and paint/stain decks. We will take care of all your flooring needs. Install cabinets and countertops. Handyman services for about anything you are needing done.

We take care of all your Home Remodeling and Repair needs, big or small. We offer drywall services, plastering, painting. We build, repair and paint/stain decks. We will take care of all your flooring needs. Install cabinets and countertops. Handyman services for about anything you are needing done.

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Tankless water heater installations FAQs

Yes, although they have a higher upfront cost compared to traditional units, tankless water heaters can be worth the investment for many homeowners. They heat water on demand, eliminating standby energy losses and leading to 24% to 34% greater energy efficiency for homes using up to 41 gallons of hot water daily. Tankless units last longer—around 20 years with proper maintenance—and require less space than traditional units. They also reduce the risk of leaks and water damage since there's no tank to corrode and fail.

Tankless water heaters, including gas-powered models, do require electricity to operate components like the ignition and control systems. This means they won't function during a power outage. If you live in an area prone to outages and want to ensure a continuous hot water supply, consider installing a battery backup system or generator to keep your tankless water heater running when the power goes out.

You should set your tankless water heater to 120 degrees Fahrenheit for optimal safety and efficiency, as recommended by the U.S. Consumer Product Safety Commission. Setting the temperature at 120 degrees prevents scalding accidents, particularly for children and the elderly, and reduces energy consumption. Temperatures above 140 degrees increase the risk of burns and promote mineral buildup, which can decrease the system's efficiency.

A 20-minute shower uses 50 to 60 gallons of water, assuming a flow rate of 2.5 to 3 gallons per minute. A typical whole-house tankless water heater can produce 4 to 8 gallons of hot water per minute, providing continuous hot water for long showers. By installing low-flow showerheads and reducing shower time, you decrease water consumption and energy costs, maximizing the efficiency of your tankless system.

With proper maintenance, a tankless water heater lasts around 20 years, significantly longer than conventional tank water heaters, which last between 8 and 12 years. Regular inspections and timely repairs can further extend its lifespan. To keep your tankless system operating efficiently, have it inspected or serviced annually and address any minor issues promptly by contacting a local tankless water heater repair service.

The homeowners guide to tankless water heater installations
From average costs to expert advice, get all the answers you need to get your job done.
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