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Tankless water heater repair pros in Mount Sinai

Avatar for Energywise, Inc.
Energywise, Inc.
2231 5th Avenue
New on HomeAdvisorNew on Angi
Approved Pro
Energywise, Inc.
2231 5th Avenue
New on AngiNew on HomeAdvisor
Approved Pro
40 years of experience
Emergency services offered

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumers 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.

We take great pride in our experience, expertise, quality, and customer service that we provide to meet the consumers 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.


Avatar for 1-800-Plumber +Air of Central Long Island
1-800-Plumber +Air of Central Long Island
36 Gazza Boulevard
5.00(
6
)
Approved Pro
1-800-Plumber +Air of Central Long Island
36 Gazza Boulevard
5.00(
6
)
Approved Pro
Customers say: Quick response
186 local quotes requested
1 years of experience

1-800-Plumber + Air of Central Long Island is focused on being the BEST! It's not about being better than everyone else, instead our focus is on providing you with the fast, dependable plumbing and emergency services when you need it most. Our goal is to give you the BEST experience you have ever received from a service based business.

"Greg fixed dryer vent clog, bathroom sink leak, and outdoor hose spigot drip to perfection! Greg was very professional, used shoe covers, took care not to damage any property, and left everything spotless. As the homeowner, the service was outstanding and the price reasonable. Catherine Martin"

Catherine M on April 2025

1-800-Plumber + Air of Central Long Island is focused on being the BEST! It's not about being better than everyone else, instead our focus is on providing you with the fast, dependable plumbing and emergency services when you need it most. Our goal is to give you the BEST experience you have ever received from a service based business.

"Greg fixed dryer vent clog, bathroom sink leak, and outdoor hose spigot drip to perfection! Greg was very professional, used shoe covers, took care not to damage any property, and left everything spotless. As the homeowner, the service was outstanding and the price reasonable. Catherine Martin"

Catherine M on April 2025


Avatar for Tedco Group, Inc.
Tedco Group, Inc.
140 North 9th Street
4.54(
323
)
Approved Pro
Tedco Group, Inc.
140 North 9th Street
4.54(
323
)
Approved Pro
Customers say: Quality work
Recommended by 92% of Angi customers
Recommended by 92% of HomeAdvisor customers
15 years of experience

We are dedicated to providing our clients with the very best in service, installation, and repair for your heating and cooling needs. We are a locally owned and operated company that values honesty and integrity. We specialize in central A/C and cooling systems as well as heating and furnace systems. We take pride in the quality of our work and our commitment to outstanding results and look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Fantastic service. Job was completed quickly, and staff was clean."

Panagiotis S on May 2025

We are dedicated to providing our clients with the very best in service, installation, and repair for your heating and cooling needs. We are a locally owned and operated company that values honesty and integrity. We specialize in central A/C and cooling systems as well as heating and furnace systems. We take pride in the quality of our work and our commitment to outstanding results and look forward to building long-term relationships with our clients, and guarantee your satisfaction.

"Fantastic service. Job was completed quickly, and staff was clean."

Panagiotis S on May 2025


Avatar for Varsity Home Service Company, Inc.
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
186
)
Approved Pro
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
186
)
Approved Pro
Customers say: Quality work
Recommended by 90% of Angi customers
Recommended by 90% of HomeAdvisor customers
431 local quotes requested

Practice makes perfect, and Varsity has been at it for over half a century! What began with a Navy veteran’s simple dream — to teach the value of honest, hands-on work to his children — has grown into one of Long Island’s most trusted resource for plumbing, heating and air conditioning services. Varsity’s mission has always been clear: to serve our neighbors with integrity, solve home service challenges with innovative solutions, and provide lasting results. Our dedicated crew is background-checked, rigorously trained in the latest technology, and excited to exceed your expectations. Above all Varsity is here to EARN your trust—not just for today, but for years to come. Let’s tackle your home service needs with the quality and care you deserve!

"Prompt and professional. Thanks."

Justin S on May 2025

Practice makes perfect, and Varsity has been at it for over half a century! What began with a Navy veteran’s simple dream — to teach the value of honest, hands-on work to his children — has grown into one of Long Island’s most trusted resource for plumbing, heating and air conditioning services. Varsity’s mission has always been clear: to serve our neighbors with integrity, solve home service challenges with innovative solutions, and provide lasting results. Our dedicated crew is background-checked, rigorously trained in the latest technology, and excited to exceed your expectations. Above all Varsity is here to EARN your trust—not just for today, but for years to come. Let’s tackle your home service needs with the quality and care you deserve!

"Prompt and professional. Thanks."

Justin S on May 2025


Avatar for BuildRite Pro Inc.
BuildRite Pro Inc.
Suffolk County
4.11(
19
)
Approved Pro
BuildRite Pro Inc.
Suffolk County
4.11(
19
)
Approved Pro
1476 local quotes requested
Free onsite estimate

Here at Bawa Construction Group, we sustain our business on quality and integrity. We are experts in general contracting specializing in all types of remodeling, Concrete work, Hardscaping/Pavers, Kitchen/Bath/ and Basements. We are committed to providing quality services from the beginning to the end of your project or scope of work. We look forward to earning your business. We also offer financing options to all customers dealing with 30+ banks and lenders. Book your FREE ESTIMATE today!!!

"Didn’t make good on a project gone bed."

Gale M on February 2024

Here at Bawa Construction Group, we sustain our business on quality and integrity. We are experts in general contracting specializing in all types of remodeling, Concrete work, Hardscaping/Pavers, Kitchen/Bath/ and Basements. We are committed to providing quality services from the beginning to the end of your project or scope of work. We look forward to earning your business. We also offer financing options to all customers dealing with 30+ banks and lenders. Book your FREE ESTIMATE today!!!

"Didn’t make good on a project gone bed."

Gale M on February 2024


Avatar for Classic Remodeling Group Inc
Classic Remodeling Group Inc
1839 Bellmore Ave
4.79(
43
)
Approved Pro
Classic Remodeling Group Inc
1839 Bellmore Ave
4.79(
43
)
Approved Pro
Super Service Award
Customers say: Super punctual
Recommended by 95% of Angi customers
Recommended by 95% of HomeAdvisor customers
2415 local quotes requested

Full service remodeling, roofing and siding contractors serving Long Island. Whether you are in need of new roof installation, roof restoration, or roof repairs; new siding installation, siding repairs; new windows & doors installation; kitchen remodeling; bathroom remodeling; we are the Long Island home remodeling contractors to call, due to our professionalism and affordability.

"John and his crew did a fabulous job renovating my bathroom. It was done in a timely manner and they were extremely neat and cleaned up very well after themselves. I would definitely hire them again!"

Denise S on March 2025

Full service remodeling, roofing and siding contractors serving Long Island. Whether you are in need of new roof installation, roof restoration, or roof repairs; new siding installation, siding repairs; new windows & doors installation; kitchen remodeling; bathroom remodeling; we are the Long Island home remodeling contractors to call, due to our professionalism and affordability.

"John and his crew did a fabulous job renovating my bathroom. It was done in a timely manner and they were extremely neat and cleaned up very well after themselves. I would definitely hire them again!"

Denise S on March 2025


Avatar for JBL HOME IMPROVEMENTS INC
JBL HOME IMPROVEMENTS INC
PO BOX 584
4.67(
255
)
Approved Pro
JBL HOME IMPROVEMENTS INC
PO BOX 584
4.67(
255
)
Approved Pro
Super Service Award
Customers say: Quality work
Recommended by 90% of Angi customers
Recommended by 90% of HomeAdvisor customers
2101 local quotes requested

JBL Home Improvements, Inc, located in St. James, is a family owned and operated remodeling business specializing in residential projects. Owner & Contractor David Kaplan, General Manager Jill Kaplan, along with their team of talented professionals, are dedicated to providing outstanding workmanship and customer service to homeowners who live in their community.

"JBL Home Improvements is a great company to work with. Dave and Jill are friendly, helpful, reliable and punctual! When they stay they will start, the do. They are there early each day and keep things as tidy as possible. For our recent job they finished just 1 day past the expected time-frame. Considering the many stories you probably have heard - the timing was spot on! They have great resources and talented workers who did an excellent job installing new floors and a new set of stairs, as well as new doors, sheet rock and molding! Highly recommend using JBL Home Improvements!"

Jeff G on March 2025

JBL Home Improvements, Inc, located in St. James, is a family owned and operated remodeling business specializing in residential projects. Owner & Contractor David Kaplan, General Manager Jill Kaplan, along with their team of talented professionals, are dedicated to providing outstanding workmanship and customer service to homeowners who live in their community.

"JBL Home Improvements is a great company to work with. Dave and Jill are friendly, helpful, reliable and punctual! When they stay they will start, the do. They are there early each day and keep things as tidy as possible. For our recent job they finished just 1 day past the expected time-frame. Considering the many stories you probably have heard - the timing was spot on! They have great resources and talented workers who did an excellent job installing new floors and a new set of stairs, as well as new doors, sheet rock and molding! Highly recommend using JBL Home Improvements!"

Jeff G on March 2025


Avatar for Verma Contracting
Verma Contracting
94 Broadway
5.00(
3
)
Approved Pro
Verma Contracting
94 Broadway
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
1439 local quotes requested

Hello future customers. We are a locally owned construction company that is located out of Hicksville NY. Our team of professionals have over 10 years of hands on experience. We specialize in satisfying all of our customers. Allow our team of builders, designers, and architects help provide you with what you are looking for. Contact us today for your free estimate. We are known for our neatly done work that brings satisfaction to all our customers. "Do it once and do it right".

"It was a small project and the owner of the company completed it. He took his time to do the project right and he is very careful to keep my home clean."

Eric R on October 2023

Hello future customers. We are a locally owned construction company that is located out of Hicksville NY. Our team of professionals have over 10 years of hands on experience. We specialize in satisfying all of our customers. Allow our team of builders, designers, and architects help provide you with what you are looking for. Contact us today for your free estimate. We are known for our neatly done work that brings satisfaction to all our customers. "Do it once and do it right".

"It was a small project and the owner of the company completed it. He took his time to do the project right and he is very careful to keep my home clean."

Eric R on October 2023


Avatar for J R B & SON INC
J R B & SON INC
46 Charm City Drive
5.00(
41
)
Approved Pro
J R B & SON INC
46 Charm City Drive
5.00(
41
)
Approved Pro
Super Service Award
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
176 local quotes requested

Over 40 years experience in remodeling bathrooms and kitchens Welcome to J R B & Son, Inc we have over 40 years experience in total bathroom renovations. We proudly provide the highest quality of service and craftsmanship for each aspect of your project. Our depth of knowledge and experience solidify our belief that customer service stands as the highest priority. We eagerly look forward to working with you, and making your vision a reality. Give us a call, text or email today, and let us get started!. I am so confident about our workmanship NO MONEY UPFONT, NO MONEY DOWN, YOU PAY ME ON COMPLETION No other contractor will do this. PLEASE READ OUR REVIEWS.

"We recently had our bathroom renovated and are very happy with the results. From start to finish, John was professional, reliable, and skilled. He took the time to listen to our vision, made thoughtful suggestions, and executed with precision. The workspace was kept clean, they stayed on schedule, and communicated clearly every step of the way. We highly recommend John and his team to anyone looking for an stress-free, high-quality bathroom renovation. We will absolutely be hiring them again for future projects!"

Jason Sher N on May 2025

Over 40 years experience in remodeling bathrooms and kitchens Welcome to J R B & Son, Inc we have over 40 years experience in total bathroom renovations. We proudly provide the highest quality of service and craftsmanship for each aspect of your project. Our depth of knowledge and experience solidify our belief that customer service stands as the highest priority. We eagerly look forward to working with you, and making your vision a reality. Give us a call, text or email today, and let us get started!. I am so confident about our workmanship NO MONEY UPFONT, NO MONEY DOWN, YOU PAY ME ON COMPLETION No other contractor will do this. PLEASE READ OUR REVIEWS.

"We recently had our bathroom renovated and are very happy with the results. From start to finish, John was professional, reliable, and skilled. He took the time to listen to our vision, made thoughtful suggestions, and executed with precision. The workspace was kept clean, they stayed on schedule, and communicated clearly every step of the way. We highly recommend John and his team to anyone looking for an stress-free, high-quality bathroom renovation. We will absolutely be hiring them again for future projects!"

Jason Sher N on May 2025


Avatar for Islandwide Contracting
Islandwide Contracting
23 Union Avenue
5.00(
1
)
Approved Pro
Islandwide Contracting
23 Union Avenue
5.00(
1
)
Approved Pro
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
445 local quotes requested

​At Islandwide Contracting LLC, we have been proudly serving Suffolk County and surrounding areas since 2019, bringing over 30 years of combined experience to every project. Our comprehensive range of residential and commercial construction services includes interior and exterior work, such as medical offices, restaurants, urgent care facilities, dormers, and extensions. We specialize in bathroom and kitchen renovations, as well as basement transformations. Contact us today for a free estimate at 631-779-9277, and let us help you build the dream you envision. ​**At Islandwide Contracting, we deeply appreciate the dedication and sacrifices of our military personnel, first responders, and senior citizens. As a token of our gratitude, we are proud to offer special discounts tailored specifically for these esteemed groups. Please inquire about these exclusive offers when you contact us, and let us assist you in bringing your vision to life.**

"Islandwide Contracting did an amazing job for our new medical facility in Holbrook. We have gotten tons of compliments for their high quality work. Definitely would rehire them again! Thank you to Andrew and his team."

Sayed K on March 2025

​At Islandwide Contracting LLC, we have been proudly serving Suffolk County and surrounding areas since 2019, bringing over 30 years of combined experience to every project. Our comprehensive range of residential and commercial construction services includes interior and exterior work, such as medical offices, restaurants, urgent care facilities, dormers, and extensions. We specialize in bathroom and kitchen renovations, as well as basement transformations. Contact us today for a free estimate at 631-779-9277, and let us help you build the dream you envision. ​**At Islandwide Contracting, we deeply appreciate the dedication and sacrifices of our military personnel, first responders, and senior citizens. As a token of our gratitude, we are proud to offer special discounts tailored specifically for these esteemed groups. Please inquire about these exclusive offers when you contact us, and let us assist you in bringing your vision to life.**

"Islandwide Contracting did an amazing job for our new medical facility in Holbrook. We have gotten tons of compliments for their high quality work. Definitely would rehire them again! Thank you to Andrew and his team."

Sayed K on March 2025

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Tankless water heater installations FAQs

Professional flushing services for tankless water heaters run about $200 per visit. This essential maintenance procedure eliminates mineral deposits from critical components, particularly the heat exchanger. While homeowners can purchase DIY flushing kits for $50 to $100, professional service offers the advantage of thorough cleaning with proper techniques. Professional maintenance also includes inspection of additional components that might need attention.

Industry experts and manufacturers recommend annual maintenance for tankless water heaters, with more frequent service (every six months) for homes with challenging water conditions. This regular attention prevents efficiency losses and extends the unit's operational lifespan. Watch for warning signs like reduced water temperature, inconsistent performance, or system error codes that might indicate maintenance is needed sooner than scheduled.

Neglecting regular maintenance allows mineral scale to accumulate within your system, restricting water flow and reducing heating efficiency. This forces your unit to work harder, consuming more energy while delivering less satisfactory performance. Over time, this strain can lead to component failures, inconsistent water temperatures, and premature system replacement. Additionally, most manufacturers require documentation of regular maintenance to honor warranty coverage for major components.

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