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Tankless water heater repair pros in Mastic

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 RDS Plumbing and Heating
RDS Plumbing and Heating
1303 Waverly Avenue
4.92(
79
)
Approved Pro
RDS Plumbing and Heating
1303 Waverly Avenue
4.92(
79
)
Approved Pro
Customers say: True professional
8 years of experience

Please visit us at www.rdsplumbingheating.com for more info. We pride our company on reliability, great communication, integrity, quality work and beating our competitors pricing on all work. Being experts in the plumbing and heating trade for over 20 years we can quickly diagnose your issue and make the necessary repairs or installations to remedy the problem. This gives us the ability to be competitively priced, ensuring your problem is fixed the first time ! RDS looks forward to gaining you as life long customer. Give us a call 631-590-0561

"My Pro "Rich" at RDS Plumbing and Heating showed photos of similar systems he'd installed, negotiated a fair price and did everything he said he would do and cleaned up after he was done. I couldn't have asked for more."

John J L on July 2025

Please visit us at www.rdsplumbingheating.com for more info. We pride our company on reliability, great communication, integrity, quality work and beating our competitors pricing on all work. Being experts in the plumbing and heating trade for over 20 years we can quickly diagnose your issue and make the necessary repairs or installations to remedy the problem. This gives us the ability to be competitively priced, ensuring your problem is fixed the first time ! RDS looks forward to gaining you as life long customer. Give us a call 631-590-0561

"My Pro "Rich" at RDS Plumbing and Heating showed photos of similar systems he'd installed, negotiated a fair price and did everything he said he would do and cleaned up after he was done. I couldn't have asked for more."

John J L on July 2025


Avatar for Varsity Home Service Company, Inc.
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
188
)
Approved Pro
Varsity Home Service Company, Inc.
1610 Ocean Avenue
4.78(
188
)
Approved Pro
Customers say: Quality work
566 local quotes requested
63 years of experience

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!

"Coming out next week to repair A/C unit"

Tom M 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!

"Coming out next week to repair A/C unit"

Tom M on June 2025


Avatar for Islandwide Contracting
Islandwide Contracting
23 Union Avenue
5.00(
3
)
Approved Pro
Islandwide Contracting
23 Union Avenue
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
567 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.**

"Excellent. Workers were neat respectful and I was very happy with the results I will be using the company again for any work needed in my home."

Cathy V on June 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.**

"Excellent. Workers were neat respectful and I was very happy with the results I will be using the company again for any work needed in my home."

Cathy V on June 2025


Avatar for JBL HOME IMPROVEMENTS INC
JBL HOME IMPROVEMENTS INC
PO BOX 584
4.67(
257
)
Approved Pro
JBL HOME IMPROVEMENTS INC
PO BOX 584
4.67(
257
)
Approved Pro
Customers say: Quality work
Recommended by 90% of Angi customers
Recommended by 90% of HomeAdvisor customers
1865 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.

"I am very pleased with my remodel. Dave was professional and his crew were on time, worked every day and took care of my house like it was their own!"

Jennie D on July 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.

"I am very pleased with my remodel. Dave was professional and his crew were on time, worked every day and took care of my house like it was their own!"

Jennie D on July 2025


Avatar for Cesspools R Us
Cesspools R Us
Lindenhurst,
5.00(
8
)
Approved Pro
Cesspools R Us
Lindenhurst,
5.00(
8
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
709 local quotes requested

Cesspools R Us, led by owner Janet Russo, is a family-owned and operated business proudly serving Lindenhurst, NY, and the surrounding areas. Specializing in all aspects of septic work, Cesspools R Us offers comprehensive solutions for both cesspool and septic systems, as well as sewer and drain cleaning services. With a deep understanding of the unique septic needs in this area, our team is dedicated to delivering quality installations, services, and maintenance for residential and commercial systems. As a full-service cesspool, sewer, and drain company, Cesspools R Us holds certification from the New York State Department of Environmental Conservation, ensuring trusted expertise and commitment to environmental standards. From new installations to routine cleanings and emergency repairs, we are here to keep your septic systems functioning optimally. Reach out to us at 631-873-6162 for reliable, professional service you can count on.

"Frank was very knowledgeable, friendly, and fixed our clog in no time. Prompt service, and on time. Will definitely hire again if needed."

Alicia i on January 2025

Cesspools R Us, led by owner Janet Russo, is a family-owned and operated business proudly serving Lindenhurst, NY, and the surrounding areas. Specializing in all aspects of septic work, Cesspools R Us offers comprehensive solutions for both cesspool and septic systems, as well as sewer and drain cleaning services. With a deep understanding of the unique septic needs in this area, our team is dedicated to delivering quality installations, services, and maintenance for residential and commercial systems. As a full-service cesspool, sewer, and drain company, Cesspools R Us holds certification from the New York State Department of Environmental Conservation, ensuring trusted expertise and commitment to environmental standards. From new installations to routine cleanings and emergency repairs, we are here to keep your septic systems functioning optimally. Reach out to us at 631-873-6162 for reliable, professional service you can count on.

"Frank was very knowledgeable, friendly, and fixed our clog in no time. Prompt service, and on time. Will definitely hire again if needed."

Alicia i on January 2025


Avatar for Allied Construction Corp
Allied Construction Corp
26 Pagnotta Dr
4.45(
161
)
Approved Pro
Allied Construction Corp
26 Pagnotta Dr
4.45(
161
)
Approved Pro
Customers say: True professional
1215 local quotes requested
36 years of experience

**We are now specializing in Kitchen Remodeling**At this time we are unable to take on Bathroom Remodeling projects**Our first priority has always been the satisfaction of our customers, and we take great pride in both the quality of our work and the quality of the customer service we extend to each and every one of our clients, regardless of the size of their project. When trusting Allied Construction Corporation with your home remodeling project, you are trusting a crew of dedicated and talented home remodeling experts to take you through every single step of the process, and to keep you up to date on developments. We always treat your project – and your home – with the utmost level of care and respect. We strive to ensure that every last detail of your work order is performed with the same level of quality we would apply to our own home. Our work over the years has proven to yield exceptionally high return on investment, making your home not only the haven you envisioned but also more valuable. What is more, we provide extremely affordable home remodeling services, making it possible for you to see your vision come to life without breaking the bank. We also offer Angie's List members a 10% Discount on all Labor. We have been on the Discovery Channel. (References upon request). Additional Phone: 516-500-8170 Additional email: alliedgcinc@aol.com.

"RUN FAR AWAY FROM ALLIED AND TOM. Tom took my money and did not complete the renovations as per our contract. He lied about having a licensed electrician to do electrical work, it was just one of his workers who's not licensed. I paid for a dumpster and when it was delivered by tom it was already half full from another allied job and I was asked to pay the full amount of $950. Tom didn't listen to anything I said regarding the work I requested and he changed my design and did work that was cheaper for him. I was priced for one of my ceiling's to be ripped out and reinstalled with new sheetrock, Tom waited until I was away on business then he installed sheetrock on top of the bad sheetrock and told me he ripped out the old sheetrock and installed the new sheetrock, I found out when my EC cut holes to install lights and we found 2 layers of sheetrock preventing the lights from being able to be installed. Allied construction is a cheap, sneaky company who will steal your money and breach your contract. Do not hire these people Tom is a lair. Tom wore a gun in my house on his hip and told me "I use this to get paid by customer who don't want to pay". Tom left live 120v wires hanging out of the walls and ceiling, he removed a banister and didn't replace it for 3 weeks making my home very unsafe for me and my 9 year old son."

Adam C on May 2025

**We are now specializing in Kitchen Remodeling**At this time we are unable to take on Bathroom Remodeling projects**Our first priority has always been the satisfaction of our customers, and we take great pride in both the quality of our work and the quality of the customer service we extend to each and every one of our clients, regardless of the size of their project. When trusting Allied Construction Corporation with your home remodeling project, you are trusting a crew of dedicated and talented home remodeling experts to take you through every single step of the process, and to keep you up to date on developments. We always treat your project – and your home – with the utmost level of care and respect. We strive to ensure that every last detail of your work order is performed with the same level of quality we would apply to our own home. Our work over the years has proven to yield exceptionally high return on investment, making your home not only the haven you envisioned but also more valuable. What is more, we provide extremely affordable home remodeling services, making it possible for you to see your vision come to life without breaking the bank. We also offer Angie's List members a 10% Discount on all Labor. We have been on the Discovery Channel. (References upon request). Additional Phone: 516-500-8170 Additional email: alliedgcinc@aol.com.

"RUN FAR AWAY FROM ALLIED AND TOM. Tom took my money and did not complete the renovations as per our contract. He lied about having a licensed electrician to do electrical work, it was just one of his workers who's not licensed. I paid for a dumpster and when it was delivered by tom it was already half full from another allied job and I was asked to pay the full amount of $950. Tom didn't listen to anything I said regarding the work I requested and he changed my design and did work that was cheaper for him. I was priced for one of my ceiling's to be ripped out and reinstalled with new sheetrock, Tom waited until I was away on business then he installed sheetrock on top of the bad sheetrock and told me he ripped out the old sheetrock and installed the new sheetrock, I found out when my EC cut holes to install lights and we found 2 layers of sheetrock preventing the lights from being able to be installed. Allied construction is a cheap, sneaky company who will steal your money and breach your contract. Do not hire these people Tom is a lair. Tom wore a gun in my house on his hip and told me "I use this to get paid by customer who don't want to pay". Tom left live 120v wires hanging out of the walls and ceiling, he removed a banister and didn't replace it for 3 weeks making my home very unsafe for me and my 9 year old son."

Adam C on May 2025


Master Remodelers
Covering Suffolk County
5.00(
7
)
Approved Pro
Master Remodelers
Covering Suffolk County
5.00(
7
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
692 local quotes requested

We pride ourselves on the quality work we provide, while delivering great customer service. Check out our services offered and call or click to schedule an estimate today!

"Master remodelers did a fantastic job without any complications. Joe and the team were very professional and efficient. My kitchen looks beautiful. Highly Recommend!"

Kathleen M on May 2025

We pride ourselves on the quality work we provide, while delivering great customer service. Check out our services offered and call or click to schedule an estimate today!

"Master remodelers did a fantastic job without any complications. Joe and the team were very professional and efficient. My kitchen looks beautiful. Highly Recommend!"

Kathleen M on May 2025


Avatar for Kitchen & Bath Works INC
Kitchen & Bath Works INC
1551 LIincoln Ave
5.00(
101
)
Approved Pro
Kitchen & Bath Works INC
1551 LIincoln Ave
5.00(
101
)
Approved Pro
Customers say: Quick response
Recommended by 99% of Angi customers
Recommended by 99% of HomeAdvisor customers
537 local quotes requested

Kitchen and Bath Works Inc has been owner operated and successfully in business since 1994. Offering a consultative approach and delivering on quality, custom work, our business has been overwhelmingly driven by word of mouth referrals. From start to finish, we stand by our work and our owner is committed to being present on all jobs.

"Lou renovated my kitchen last year and I was completely satisfied. I called him back this summer to gut and remodel my bathroom. He was extremely considerate, and he treated my house as if it were his own. My house is small, and I only have one bathroom. The project took nine days. I was anticipating that there would be a big mess and a huge inconvenience. But even the demo was done very neatly and efficiently. Lou even took the time to re-connect the toilet each night so that I wouldn't be left without. Lou did an amazing job, and it was a pleasure working with him. Once again, I am pleased to recommend Lou for your kitchen or bath project."

Janet M on November 2023

Kitchen and Bath Works Inc has been owner operated and successfully in business since 1994. Offering a consultative approach and delivering on quality, custom work, our business has been overwhelmingly driven by word of mouth referrals. From start to finish, we stand by our work and our owner is committed to being present on all jobs.

"Lou renovated my kitchen last year and I was completely satisfied. I called him back this summer to gut and remodel my bathroom. He was extremely considerate, and he treated my house as if it were his own. My house is small, and I only have one bathroom. The project took nine days. I was anticipating that there would be a big mess and a huge inconvenience. But even the demo was done very neatly and efficiently. Lou even took the time to re-connect the toilet each night so that I wouldn't be left without. Lou did an amazing job, and it was a pleasure working with him. Once again, I am pleased to recommend Lou for your kitchen or bath project."

Janet M on November 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
717 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.

"Excellent, exceptional, and overall a wonderful kitchen face lift job. Painted cabinets, new tile floor, new quartz counter tops and backsplash. Updated lighting and a fresh paint job throughout. Highly recommend, we would gladly have have company back for projects in the future."

Susan Volpe And Harry F on February 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.

"Excellent, exceptional, and overall a wonderful kitchen face lift job. Painted cabinets, new tile floor, new quartz counter tops and backsplash. Updated lighting and a fresh paint job throughout. Highly recommend, we would gladly have have company back for projects in the future."

Susan Volpe And Harry F on February 2025

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FAQs for tankless water heater installation projects in Mastic, 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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