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Tankless water heater repair pros in West Islip

Avatar for Islandwide Plumbing and Heating, LLC
Islandwide Plumbing and Heating, LLC
170 Delaware Avenue
5.00(
1
)
Approved Pro
Islandwide Plumbing and Heating, LLC
170 Delaware Avenue
5.00(
1
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
17 years of experience

At Islandwide Plumbing and Heating LLC I pride my company on reliability, great communication, integrity, and quality work. I am an expert in my trade and will do my best to keep you as educated as I can on your particular task or project. I look forward to earning your business!

"He is an awesome guy to work with! I would highly recommend him!"

Todd Y on August 2020

At Islandwide Plumbing and Heating LLC I pride my company on reliability, great communication, integrity, and quality work. I am an expert in my trade and will do my best to keep you as educated as I can on your particular task or project. I look forward to earning your business!

"He is an awesome guy to work with! I would highly recommend him!"

Todd Y on August 2020


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 Brandon Electric
Brandon Electric
56 Elm Drive North
4.88(
167
)
Approved Pro
Brandon Electric
56 Elm Drive North
4.88(
167
)
Approved Pro
Super Service Award
Customers say: True professional
Recommended by 97% of Angi customers
Recommended by 97% of HomeAdvisor customers
24 local quotes requested

Brandon specialize in HVAC [multi zone central air-condition system ,heat pump, swimming pool heater, mini split, wine cellar cooling system, gas or oil boiler and furnace ]repaired and installation and also do smart thermostat,wi-fi bridge stem , smart water main valve installations, .We take pride in our quality of work and our commitment to outstanding results. We are committed to providing a personalized service for each individual project we take on. We look forward to building strong, long-term relationships with our clients and guarantee your satisfaction.

"Brandon was great. He came and diagnosed my pool heater on Memorial day weekend. He sent me a link to order the needed part. Part came, Brandon came back same week and installed the part. Heater works great. Would highly recommend Brandon. "

Bill R on May 2025

Brandon specialize in HVAC [multi zone central air-condition system ,heat pump, swimming pool heater, mini split, wine cellar cooling system, gas or oil boiler and furnace ]repaired and installation and also do smart thermostat,wi-fi bridge stem , smart water main valve installations, .We take pride in our quality of work and our commitment to outstanding results. We are committed to providing a personalized service for each individual project we take on. We look forward to building strong, long-term relationships with our clients and guarantee your satisfaction.

"Brandon was great. He came and diagnosed my pool heater on Memorial day weekend. He sent me a link to order the needed part. Part came, Brandon came back same week and installed the part. Heater works great. Would highly recommend Brandon. "

Bill R on May 2025


Avatar for J.A.D Mechanical
J.A.D Mechanical
1075 Steel Boulevard
5.00(
7
)
Approved Pro
J.A.D Mechanical
1075 Steel Boulevard
5.00(
7
)
Approved Pro
27 years of experience
Free onsite estimate

With over 24 years of experience, J.A.D. Mechanical, 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. Call us today!

"Ralphie was quick and extremely efficient with the work. The cleanliness and accuracy of the work was admirable. Highly recommend!! "

Sahiba R on June 2025

With over 24 years of experience, J.A.D. Mechanical, 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. Call us today!

"Ralphie was quick and extremely efficient with the work. The cleanliness and accuracy of the work was admirable. Highly recommend!! "

Sahiba R on June 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 All Weather Heating & Cooling
All Weather Heating & Cooling
35 COURT ST
4.68(
60
)
Approved Pro
All Weather Heating & Cooling
35 COURT ST
4.68(
60
)
Approved Pro
Customers say: Super punctual
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
2044 local quotes requested

All Weather Heating & Cooling has been serving Nassau & Suffolk County of Long Island since 1969. We are now celebrating 54 years of exceeding customer expectations. All Weather provides sales, installation, service and maintenance of residential and commercial heating, air conditioning & water filtration systems.

"They installed a minisplit cooling system, with 3 exchanges June 2021. Since then it is not operating the way it should. In my bedroom with the door closed at night on cool at 70 degrees the humidity goes up to 80%. I wake up uncomfortable, change it from cool to dry mode. The humidity will go down into the 50% range but the temperature drops down to 62 or less! So in cool or dry mode I can't get a good nights sleep! They come and look at it and tell me everything is fine. I'm going to buy a window air conditioner tomorrow which seems insane because i spent $10,000 on this minisplit AC system!"

JIM G on June 2023

All Weather Heating & Cooling has been serving Nassau & Suffolk County of Long Island since 1969. We are now celebrating 54 years of exceeding customer expectations. All Weather provides sales, installation, service and maintenance of residential and commercial heating, air conditioning & water filtration systems.

"They installed a minisplit cooling system, with 3 exchanges June 2021. Since then it is not operating the way it should. In my bedroom with the door closed at night on cool at 70 degrees the humidity goes up to 80%. I wake up uncomfortable, change it from cool to dry mode. The humidity will go down into the 50% range but the temperature drops down to 62 or less! So in cool or dry mode I can't get a good nights sleep! They come and look at it and tell me everything is fine. I'm going to buy a window air conditioner tomorrow which seems insane because i spent $10,000 on this minisplit AC system!"

JIM G on June 2023


Top Gun Kitchen & Cabinets
110 Brook Ave C
5.00(
13
)
Approved Pro
Top Gun Kitchen & Cabinets
110 Brook Ave C
5.00(
13
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
680 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.

"Fast clean and good work"

edward c 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.

"Fast clean and good work"

edward c 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
555 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


Avatar for Stone's Construction Corp.
Stone's Construction Corp.
1496 Broad St
4.74(
31
)
Approved Pro
Stone's Construction Corp.
1496 Broad St
4.74(
31
)
Approved Pro
Customers say: Quality work
Recommended by 96% of Angi customers
Recommended by 96% of HomeAdvisor customers
523 local quotes requested

Stone's Construction has been in business since 1986. We are fully insured and have a clean record with Consumer Affairs. Our estimates are free and you deal with the owner. The company continuously provides customers with the best quality and value for the best prices out there. We specialize in Dormers,Extensions,Kitchens,Bathrooms,Basements,Siding, House Lifting, Porticos, Masonry

"I gave a deposit to start a job. A contract was never signed and work was never started. I decided to go in a different direction, Provider initially offered only a $250 refund, I deemed that unacceptable. Provider now has not responded to any attempted communication since approximately May 7."

vincent p on May 2025

Stone's Construction has been in business since 1986. We are fully insured and have a clean record with Consumer Affairs. Our estimates are free and you deal with the owner. The company continuously provides customers with the best quality and value for the best prices out there. We specialize in Dormers,Extensions,Kitchens,Bathrooms,Basements,Siding, House Lifting, Porticos, Masonry

"I gave a deposit to start a job. A contract was never signed and work was never started. I decided to go in a different direction, Provider initially offered only a $250 refund, I deemed that unacceptable. Provider now has not responded to any attempted communication since approximately May 7."

vincent p 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
2042 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

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FAQs for tankless water heater installation projects in West 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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