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Tankless water heater repair pros in Central Islip

Avatar for Mr. Big Plumbing & Heating
Mr. Big Plumbing & Heating
38 Brefni Street
4.88(
13
)
Approved Pro
Mr. Big Plumbing & Heating
38 Brefni Street
4.88(
13
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
3 years of experience

Big Plumbing and Heating, Inc., is your local contractor with over 20 years experience in taking care of all your needs. We do installs and service work for Suffolk and Nassau Counties. Call Today!

"Andre is very knowledgeable about the job. He not only fix the problem but also advise the necessary preventative action."

Victor P on April 2024

Big Plumbing and Heating, Inc., is your local contractor with over 20 years experience in taking care of all your needs. We do installs and service work for Suffolk and Nassau Counties. Call Today!

"Andre is very knowledgeable about the job. He not only fix the problem but also advise the necessary preventative action."

Victor P on April 2024


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 Varsity Home Service Company, Inc.
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
187
)
Approved Pro
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
187
)
Approved Pro
Customers say: Quality work
Recommended by 90% of Angi customers
Recommended by 90% of HomeAdvisor customers
487 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!

"Vinnie the rep was kind and courteous and his team did a good job on installation."

Joseph B on June 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!

"Vinnie the rep was kind and courteous and his team did a good job on installation."

Joseph B on June 2025


Avatar for HEATWAVE PLUMBING & HEATING LLC
HEATWAVE PLUMBING & HEATING LLC
109-14 139TH STREET
4.85(
20
)
Approved Pro
HEATWAVE PLUMBING & HEATING LLC
109-14 139TH STREET
4.85(
20
)
Approved Pro
Customers say: Quick response
13 local quotes requested
1 years of experience

HEATWAVE PLUMBING & HEATING LLC is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"Exceptional work done !! They finished in timely Manner and for a great price 10 out of 10 definitely recommend"

rose S on May 2025

HEATWAVE PLUMBING & HEATING LLC is committed to excellence in every aspect of our business. We uphold a standard of integrity bound by fairness, honesty, and personal responsibility. Our distinction is the quality of service we bring to our customers. Accurate knowledge of our trade combined with ability is what makes us true professionals. Above all, we are watchful of our customers' interests, and make their concerns the basis of our business.

"Exceptional work done !! They finished in timely Manner and for a great price 10 out of 10 definitely recommend"

rose S on May 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


Tri Seasonal Plumbing, Inc.
266 Middle Island Rd, Unit 13
5.00(
1
)
Approved Pro
Tri Seasonal Plumbing, Inc.
266 Middle Island Rd, Unit 13
5.00(
1
)
Approved Pro
14 local quotes requested
Free onsite estimate

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 the start to the 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.

"I had Tommy come by to fix a boiler pipe for one of my customers. Great pricing and hard working. Will continue to use them for future projects :)"

Stephan C on April 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 the start to the 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.

"I had Tommy come by to fix a boiler pipe for one of my customers. Great pricing and hard working. Will continue to use them for future projects :)"

Stephan C on April 2025


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
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
183 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 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
Customers say: Quality work
Recommended by 90% of Angi customers
Recommended by 90% of HomeAdvisor customers
2091 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.

"The project ran smoothly, on time, and on budget. Dave and his team were professional, clarified issues before they became problems, and left no loose ends. The project involved the demolition of existing built-in cabinets and a massive, green-tiled shower that was designed with one purpose in mind - growing mold. We increased the footprint of the 10x11 sq ft room by reclaiming space from an adjacent oversized walk-in closet, which made a perfect alcove for a new free-standing tub. The tile installation was done to perfection, and the installation of all components, including the neo-angle door was completed without issue. To their credit, the team helped us isolate a crack in the new Kohler toilet and installed the replacement part without complaint. We're looking forward to working with JBL on our next project."

Marc H on August 2021

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.

"The project ran smoothly, on time, and on budget. Dave and his team were professional, clarified issues before they became problems, and left no loose ends. The project involved the demolition of existing built-in cabinets and a massive, green-tiled shower that was designed with one purpose in mind - growing mold. We increased the footprint of the 10x11 sq ft room by reclaiming space from an adjacent oversized walk-in closet, which made a perfect alcove for a new free-standing tub. The tile installation was done to perfection, and the installation of all components, including the neo-angle door was completed without issue. To their credit, the team helped us isolate a crack in the new Kohler toilet and installed the replacement part without complaint. We're looking forward to working with JBL on our next project."

Marc H on August 2021


Top Gun Kitchen & Cabinets
110 Brook Ave C
5.00(
12
)
Approved Pro
Top Gun Kitchen & Cabinets
110 Brook Ave C
5.00(
12
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
663 local quotes requested

Full service Kitchen Remodeling company. Specializing in cabinet painting and kitchen face lifts with over 25 years experience. Free consultations. ZERO pressure sales. Let us save you thousands. Call today.

"Robb and his team are really pleasant and professional, they completed our kitchen cabinets with a very luxurious coating that literally transformed the space into more beautiful than we anticipated. The attention to detail is unmatched, their desire to make an outstanding space was apparent the whole way through the job! We are extremely happy and would hire them again as we have places confidence and trust in them the job will be completed Perfectly. Thank you again Robb and the guys at Top Gun, GREAT JOB! ✨"

George M on June 2025

Full service Kitchen Remodeling company. Specializing in cabinet painting and kitchen face lifts with over 25 years experience. Free consultations. ZERO pressure sales. Let us save you thousands. Call today.

"Robb and his team are really pleasant and professional, they completed our kitchen cabinets with a very luxurious coating that literally transformed the space into more beautiful than we anticipated. The attention to detail is unmatched, their desire to make an outstanding space was apparent the whole way through the job! We are extremely happy and would hire them again as we have places confidence and trust in them the job will be completed Perfectly. Thank you again Robb and the guys at Top Gun, GREAT JOB! ✨"

George M on June 2025


Bathroom Guru
77-20 Windsor Place
5.00(
5
)
Approved Pro
Bathroom Guru
77-20 Windsor Place
5.00(
5
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
543 local quotes requested

We specialize in all phases of bathroom remodels 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!

"These guys are great. New bathroom. Came out perfect no issues. I'd highly recommend for any work being done."

Kevin O on September 2023

We specialize in all phases of bathroom remodels 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!

"These guys are great. New bathroom. Came out perfect no issues. I'd highly recommend for any work being done."

Kevin O on September 2023

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FAQs for tankless water heater installation projects in Central Islip, NY

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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