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Tankless water heater repair pros in Merrimack

Avatar for Daigle Plumbing Heating and Cooling
Daigle Plumbing Heating and Cooling
11 Windham Rd
4.34(
33
)
Approved Pro
Daigle Plumbing Heating and Cooling
11 Windham Rd
4.34(
33
)
Approved Pro
Customers say: True professional
55 local quotes requested
44 years of experience

Daigle Plumbing, Heating & Cooling is family-owned and operated by the Daigle family. We are proud to provide quality, dependable plumbing, heating, and cooling services in Derry for our customers in the surrounding areas. Our crew is full of expert technicians who are ready to help you get your system up and running!

"I believe I was scammed. I had two other plumbers after job was done and they laughed at the amount of money I paid for the job. It is more than double what they would have charged me. Had I known! I also ended up signing a contract for up to a year deduction on my credit card. After I paid them more than $4,000 for less than 8 hours of work. I must have had a really bad day to have agreed to this. The gentleman was so nice that it never occurred to me that they were taking advantage of me as a senior citizen."

Irma B on June 2023

Daigle Plumbing, Heating & Cooling is family-owned and operated by the Daigle family. We are proud to provide quality, dependable plumbing, heating, and cooling services in Derry for our customers in the surrounding areas. Our crew is full of expert technicians who are ready to help you get your system up and running!

"I believe I was scammed. I had two other plumbers after job was done and they laughed at the amount of money I paid for the job. It is more than double what they would have charged me. Had I known! I also ended up signing a contract for up to a year deduction on my credit card. After I paid them more than $4,000 for less than 8 hours of work. I must have had a really bad day to have agreed to this. The gentleman was so nice that it never occurred to me that they were taking advantage of me as a senior citizen."

Irma B on June 2023


Avatar for Michael Fanjoy
Michael Fanjoy
8 Walden Dr.
5.00(
2
)
Approved Pro
Michael Fanjoy
8 Walden Dr.
5.00(
2
)
Approved Pro
Customers say: Quick response
1 years of experience
Warranties offered

Priority Plumbing is the premier plumbing service provider in the Merrimack area. Give us a call for all of your residential needs.

"I had a shower diverter valve that was custom-installed where the gaskets had failed. I found the correct part, but the installation was complex and needed a professional's touch. Mike is tremendous. He was quick to respond, worked fast, gave an accurate estimate, and put pride in his work to finish it with care. I couldn't have asked for anything more."

Brad B on October 2024

Priority Plumbing is the premier plumbing service provider in the Merrimack area. Give us a call for all of your residential needs.

"I had a shower diverter valve that was custom-installed where the gaskets had failed. I found the correct part, but the installation was complex and needed a professional's touch. Mike is tremendous. He was quick to respond, worked fast, gave an accurate estimate, and put pride in his work to finish it with care. I couldn't have asked for anything more."

Brad B on October 2024


Avatar for A Really Good Plumber
A Really Good Plumber
5 Elder Williams Rd
4.27(
11
)
Approved Pro
A Really Good Plumber
5 Elder Williams Rd
4.27(
11
)
Approved Pro
Customers say: Quality work
352 local quotes requested
18 years of experience

At A Really Good Plumber, we pride ourselves on providing our customers with reasonable pricing, quality workmanship, and professional service on every call. When you work with A Really Good Plumber, you know you are getting high quality products and exceptional service facilitated by cutting edge technology. Our certified technicians use this technology in all installations, and to diagnose, and repair existing problems. These services will ultimately benefit the ones you love by keeping you and your family comfortable and safe all year round.

"He was very observant of all the permissions needed for a gas water heater. I definitely would recommend them to anybody easy to talk to and great work."

Dave B on December 2024

At A Really Good Plumber, we pride ourselves on providing our customers with reasonable pricing, quality workmanship, and professional service on every call. When you work with A Really Good Plumber, you know you are getting high quality products and exceptional service facilitated by cutting edge technology. Our certified technicians use this technology in all installations, and to diagnose, and repair existing problems. These services will ultimately benefit the ones you love by keeping you and your family comfortable and safe all year round.

"He was very observant of all the permissions needed for a gas water heater. I definitely would recommend them to anybody easy to talk to and great work."

Dave B on December 2024


Avatar for All Work Construction INC.
All Work Construction INC.
183 Londonderry Tpke
New on HomeAdvisorNew on Angi
Approved Pro
All Work Construction INC.
183 Londonderry Tpke
New on AngiNew on HomeAdvisor
Approved Pro
981 local quotes requested
25 years of experience

All Work Construction is proudly the #1 Home Improvement Company for Hooksett NH and beyond. We specialize in bathroom remodeling, kitchen remodeling, exteriors such as vinyl siding, shingle roof replacement, replacement windows, and exterior doors. Contact us today to request our home remodeling services. We offer free estimate consultations! (We serve NH, Northern MA, and partial ME)

All Work Construction is proudly the #1 Home Improvement Company for Hooksett NH and beyond. We specialize in bathroom remodeling, kitchen remodeling, exteriors such as vinyl siding, shingle roof replacement, replacement windows, and exterior doors. Contact us today to request our home remodeling services. We offer free estimate consultations! (We serve NH, Northern MA, and partial ME)


Avatar for All Drain Services, Inc.
All Drain Services, Inc.
140 Old Derry Rd
4.85(
164
)
Approved Pro
All Drain Services, Inc.
140 Old Derry Rd
4.85(
164
)
Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
218 local quotes requested

All Drain Services, Inc. has been in the drain service business for over 18 years and is owned by Manny and Gloria Vega. Our commitment to customer service is unmatched. Our years of experience have taught us that in our line of business, that is what counts. Our dedication to delivering a quality job has been the backbone of our success, and this commitment is instilled in all our employees. All Drain Services, Inc. is open 24/7, including holidays. We offer emergency and regular maintenance services.

"Patrick was great. He pulled a Rat from my kitchen line so great service!"

Tim L on February 2023

All Drain Services, Inc. has been in the drain service business for over 18 years and is owned by Manny and Gloria Vega. Our commitment to customer service is unmatched. Our years of experience have taught us that in our line of business, that is what counts. Our dedication to delivering a quality job has been the backbone of our success, and this commitment is instilled in all our employees. All Drain Services, Inc. is open 24/7, including holidays. We offer emergency and regular maintenance services.

"Patrick was great. He pulled a Rat from my kitchen line so great service!"

Tim L on February 2023


Avatar for Armory Plumbing Inc
Armory Plumbing Inc
181 Stedman St
5.00(
5
)
Approved Pro
Armory Plumbing Inc
181 Stedman St
5.00(
5
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
1108 local quotes requested

I am a Licensed Plumber with 10 years of experience in Plumbing & Heating. With my services I provide Upfront pricing & strive to do things in a timely manner that is convenient to you. My Services include plumbing repairs, plumbing installations, Water heater replacements, Boiler Service & Installation, Bathroom/Kitchen Remodels & much more! Site visits for estimates will be $45, if you accept the estimate the site visit will be WAIVED. If you are aware of the terms & want to continue reach out to us.

"Prompt & efficient, the outcome was a 9.9 out of 10. Price was very reasonable. Jobsite clean with nothing left behind."

Richard J R on March 2025

I am a Licensed Plumber with 10 years of experience in Plumbing & Heating. With my services I provide Upfront pricing & strive to do things in a timely manner that is convenient to you. My Services include plumbing repairs, plumbing installations, Water heater replacements, Boiler Service & Installation, Bathroom/Kitchen Remodels & much more! Site visits for estimates will be $45, if you accept the estimate the site visit will be WAIVED. If you are aware of the terms & want to continue reach out to us.

"Prompt & efficient, the outcome was a 9.9 out of 10. Price was very reasonable. Jobsite clean with nothing left behind."

Richard J R on March 2025


Avatar for Long Home Products
Long Home Products
30 Centre Rd
New on HomeAdvisorNew on Angi
Approved Pro
Long Home Products
30 Centre Rd
New on AngiNew on HomeAdvisor
Approved Pro
1771 local quotes requested
80 years of experience

With over 70 years of experience in home improvement, Long Home Products is the industry-leading company you can trust to give you peace of mind. We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We are experts in all aspects of roofing, bathroom, window and door projects. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!

With over 70 years of experience in home improvement, Long Home Products is the industry-leading company you can trust to give you peace of mind. We are a locally owned and operated company that values honesty and integrity and treats your home as if it were our own. We are experts in all aspects of roofing, bathroom, window and door projects. We pride ourselves on the quality of our work as well as our commitment to outstanding results. We look forward to building lasting relationships and guarantee your satisfaction!


Avatar for Clear Water Pump & Well Service, Inc.
Clear Water Pump & Well Service, Inc.
PO Box 6
4.49(
37
)
Approved Pro
Clear Water Pump & Well Service, Inc.
PO Box 6
4.49(
37
)
Approved Pro
Customers say: Quality work
289 local quotes requested
14 years of experience

Clear Water Pump & Well Service, Inc. is your trusted partner for all your well, water filtration and pump service needs in Massachusetts and Rhode Island. With over 15 years of experience, we are the leading experts in the industry. Our commitment is to deliver exceptional service without compromising on quality, all at an affordable price. We have extensive knowledge of the latest technology in the Water Well Industry in Massachusetts and beyond, and our services are available throughout the region. Contact us today and let us earn your business.

"Good job done."

John N on November 2024

Clear Water Pump & Well Service, Inc. is your trusted partner for all your well, water filtration and pump service needs in Massachusetts and Rhode Island. With over 15 years of experience, we are the leading experts in the industry. Our commitment is to deliver exceptional service without compromising on quality, all at an affordable price. We have extensive knowledge of the latest technology in the Water Well Industry in Massachusetts and beyond, and our services are available throughout the region. Contact us today and let us earn your business.

"Good job done."

John N on November 2024


Avatar for Walley’s Heating & Air Conditioning
Walley’s Heating & Air Conditioning
35 East Hollis Street
4.80(
99
)
Approved Pro
Walley’s Heating & Air Conditioning
35 East Hollis Street
4.80(
99
)
Approved Pro
Customers say: Quick response
Recommended by 94% of Angi customers
Recommended by 94% of HomeAdvisor customers
544 local quotes requested

Walley’s is not your average HVAC contractor. From our in-house sales and support center to our modern fleet of licensed technicians, our team has the tools, trucks, and training to handle all of your mechanical needs. But more than that, we are committed to giving back and playing a bigger role in our community. Through our work with local charities, educational providers, and our continued efforts towards promoting energy-efficient products, ethical business practices, and enforcing the highest industry standards, Walley’s is delivering real value to the community every day! Our entire team is grateful for the opportunity to show you what we are made of. Thank you for your consideration.

"Badly. 2 different techs came out. We paid for a Premium service and within hours of that tech coming out, our burner stopped working completely. Mind you there is a snowstorm. They sent out a new technician and he saw nothing wrong with the system at all. He said we had no oil. He said there was no footprints even going to my intake on the side of my house. It had snowed 2 times since oil was delivered, so that makes no sense. The tech was absolutely sure we had no oil. 3 days since the first visit now and we had oil delivered and the tank filled completely. Only 150 gallons went into my 250 gallon tank. So that's wrong. And I look at the front of my furnace and now see a slow drip from the front underneath the box on the front of the furnace. First tech recommended i replace the electrodes but said it didnt need it. Second tech didnt even mention that and said our system was good. Now, I will have to contact Angi for support and my insurance company. TERRIBLE TERRIBLE TERRIBLE"

Paul C on February 2025

Walley’s is not your average HVAC contractor. From our in-house sales and support center to our modern fleet of licensed technicians, our team has the tools, trucks, and training to handle all of your mechanical needs. But more than that, we are committed to giving back and playing a bigger role in our community. Through our work with local charities, educational providers, and our continued efforts towards promoting energy-efficient products, ethical business practices, and enforcing the highest industry standards, Walley’s is delivering real value to the community every day! Our entire team is grateful for the opportunity to show you what we are made of. Thank you for your consideration.

"Badly. 2 different techs came out. We paid for a Premium service and within hours of that tech coming out, our burner stopped working completely. Mind you there is a snowstorm. They sent out a new technician and he saw nothing wrong with the system at all. He said we had no oil. He said there was no footprints even going to my intake on the side of my house. It had snowed 2 times since oil was delivered, so that makes no sense. The tech was absolutely sure we had no oil. 3 days since the first visit now and we had oil delivered and the tank filled completely. Only 150 gallons went into my 250 gallon tank. So that's wrong. And I look at the front of my furnace and now see a slow drip from the front underneath the box on the front of the furnace. First tech recommended i replace the electrodes but said it didnt need it. Second tech didnt even mention that and said our system was good. Now, I will have to contact Angi for support and my insurance company. TERRIBLE TERRIBLE TERRIBLE"

Paul C on February 2025


Avatar for Rabbit Design Remodeling Corp.
Rabbit Design Remodeling Corp.
76 Main Street Unit A
5.00(
3
)
Approved Pro
Rabbit Design Remodeling Corp.
76 Main Street Unit A
5.00(
3
)
Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
1024 local quotes requested

With over 8 years of experience as a countertop manufacturer and installer, Rabbit Design Remodeling is now also licensed as a general contractor in MA (CS-119518), making it the company you need to completely take care of your house. We will take care of everything, from the initial consultation to the last detail of the job. We will always treat your property as we would our own, and you will be amazed at how simple and easy our team will make everything go wonderfully smoothly. Call our team today. We look forward to working with you!

"Extremely well. Much better, more beautiful than I expected. This remodeling far exceeds my expectation"

Hepsie A on January 2025

With over 8 years of experience as a countertop manufacturer and installer, Rabbit Design Remodeling is now also licensed as a general contractor in MA (CS-119518), making it the company you need to completely take care of your house. We will take care of everything, from the initial consultation to the last detail of the job. We will always treat your property as we would our own, and you will be amazed at how simple and easy our team will make everything go wonderfully smoothly. Call our team today. We look forward to working with you!

"Extremely well. Much better, more beautiful than I expected. This remodeling far exceeds my expectation"

Hepsie A on January 2025

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FAQs for tankless water heater installation projects in Merrimack, NH

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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