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Water heater repair or service pros in Merrimack

Avatar for Heritage Home Service

Heritage Home Service

28 Commercial Court
4.52(
962
)
•Approved Pro

Heritage Home Service

28 Commercial Court
4.52(
962
)
•Approved Pro
Customers say: Quality work
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
187 local quotes requested

Heritage Home Service is a premier home service provider operating in New Hampshire, Massachusetts and Southern Maine. Bringing all the perks that come with having a large team while maintaining a strong focus on family-oriented service. Our namesake is about honoring those who came before us, and most importantly, it is about leaving a legacy of serving people extraordinarily well. For over 37 years in business, we have helped countless families across our community stay comfortable and healthy in their homes, and today we continue to evolve and find new ways to serve you even better.

"I had a new HVAC system installed by ( remove company name) which is now Heritage. I called Heritage about a service plan. They said a service needs to be done. I said your company just changed my filter and cleaned the system (literally a week ago). They said only the tech can sign you up so we need to do another service. I said I did not need another service. They insisted. I talked to Chris, one of the service managers and he would not budge. I called again and explained situation. Never heard back. Will not be doing business with a company that does not return phone calls when a customer is begging them to take money for a service plan. Such a poorly run company. So done with them. "

Annmarie O on June 2025

Heritage Home Service is a premier home service provider operating in New Hampshire, Massachusetts and Southern Maine. Bringing all the perks that come with having a large team while maintaining a strong focus on family-oriented service. Our namesake is about honoring those who came before us, and most importantly, it is about leaving a legacy of serving people extraordinarily well. For over 37 years in business, we have helped countless families across our community stay comfortable and healthy in their homes, and today we continue to evolve and find new ways to serve you even better.

"I had a new HVAC system installed by ( remove company name) which is now Heritage. I called Heritage about a service plan. They said a service needs to be done. I said your company just changed my filter and cleaned the system (literally a week ago). They said only the tech can sign you up so we need to do another service. I said I did not need another service. They insisted. I talked to Chris, one of the service managers and he would not budge. I called again and explained situation. Never heard back. Will not be doing business with a company that does not return phone calls when a customer is begging them to take money for a service plan. Such a poorly run company. So done with them. "

Annmarie O on June 2025

Avatar for Daigle Plumbing Heating and Cooling

Daigle Plumbing Heating and Cooling

11 Windham Rd
4.36(
34
)
•Approved Pro

Daigle Plumbing Heating and Cooling

11 Windham Rd
4.36(
34
)
•Approved Pro
Customers say: True professional
111 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!

"Great job on replacing my 50 yo oil tank."

Ellie B on August 2025

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!

"Great job on replacing my 50 yo oil tank."

Ellie B on August 2025

Avatar for All Drain Services, Inc.

All Drain Services, Inc.

140 Old Derry Rd
4.85(
165
)
•Approved Pro

All Drain Services, Inc.

140 Old Derry Rd
4.85(
165
)
•Approved Pro
Customers say: Quick response
Recommended by 93% of Angi customers
Recommended by 93% of HomeAdvisor customers
197 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.

"Joe from All Drain Services stopped by today and unclogged a drain pipe for me in the bathroom."

Wojciech G on July 2025

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.

"Joe from All Drain Services stopped by today and unclogged a drain pipe for me in the bathroom."

Wojciech G on July 2025

Avatar for Long Home Products

Long Home Products

30 Centre Rd
New on HomeAdvisorNew on HomeAdvisor
•Approved Pro

Long Home Products

30 Centre Rd
New on HomeAdvisorNew on HomeAdvisor
•Approved Pro
1654 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
350 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 One Eleven Developers

One Eleven Developers

148 Hill Road
5.00(
8
)
•Approved Pro

One Eleven Developers

148 Hill Road
5.00(
8
)
•Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
358 local quotes requested

We specialize in envisioning, designing, and building high quality kitchens and baths. Our remodeling services are simple and flexible - we tailor to your stylistic needs whether they be antique, traditional or contemporary. We are dedicated to fulfilling our promise of customer satisfaction, guaranteed.

"I am so happy that I hired One Eleven Developers and couldn't be more pleased with the outcome of the project. These guys are very knowledgable and experienced. They took pride in their work and worked hard to bring my vision to fruition. They took pride in their work and my personal satisfaction with the job really mattered to them. They listened to my ideas and offered their own suggestions based on their years of experience. In addition to their skill they were a delight to work with, they were respectful, friendly, communicative, they worked hard to keep costs down and kept me informed! I've already recommended them to a friend and hired them for more projects! If you end up choosing One Eleven Dev. you won't regret it!"

Anne S on July 2024

We specialize in envisioning, designing, and building high quality kitchens and baths. Our remodeling services are simple and flexible - we tailor to your stylistic needs whether they be antique, traditional or contemporary. We are dedicated to fulfilling our promise of customer satisfaction, guaranteed.

"I am so happy that I hired One Eleven Developers and couldn't be more pleased with the outcome of the project. These guys are very knowledgable and experienced. They took pride in their work and worked hard to bring my vision to fruition. They took pride in their work and my personal satisfaction with the job really mattered to them. They listened to my ideas and offered their own suggestions based on their years of experience. In addition to their skill they were a delight to work with, they were respectful, friendly, communicative, they worked hard to keep costs down and kept me informed! I've already recommended them to a friend and hired them for more projects! If you end up choosing One Eleven Dev. you won't regret it!"

Anne S on July 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
514 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

Ayotte Home Improvements

8 Emerson Rd
4.52(
88
)
•Approved Pro

Ayotte Home Improvements

8 Emerson Rd
4.52(
88
)
•Approved Pro
Customers say: Quality work
532 local quotes requested
20 years of experience

Ayotte Home Improvements is a fully licensed and insured remodeling/construction company. We offer free estimates and years of experience.Take a look at our website for some of our past projects.

"Bob was great- this was our first renovation as new homeowners and he helped us through the process, answering all of our questions and listening to what we wanted. We absolutely love the end result!"

John A on January 2025

Ayotte Home Improvements is a fully licensed and insured remodeling/construction company. We offer free estimates and years of experience.Take a look at our website for some of our past projects.

"Bob was great- this was our first renovation as new homeowners and he helped us through the process, answering all of our questions and listening to what we wanted. We absolutely love the end result!"

John A on January 2025

Avatar for New Style Remodeling

New Style Remodeling

5.00(
21
)
•Approved Pro

New Style Remodeling

5.00(
21
)
•Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
1035 local quotes requested

Ceramic Tile Installation & Repair, Backsplashes, Showers, Flooring, Fireplaces, Bars, Mudrooms, and more! We have the experience and dedication to bring your dreams to reality! We guarantee your satisfaction, and we won’t leave until the job is done right. Call or click to schedule a free estimate today!

"John and his crew were awesome! Can’t recommend them enough. Their work was very beautiful, efficient and clean. Will absolutely be hiring them again for future projects"

Francesca L on March 2024

Ceramic Tile Installation & Repair, Backsplashes, Showers, Flooring, Fireplaces, Bars, Mudrooms, and more! We have the experience and dedication to bring your dreams to reality! We guarantee your satisfaction, and we won’t leave until the job is done right. Call or click to schedule a free estimate today!

"John and his crew were awesome! Can’t recommend them enough. Their work was very beautiful, efficient and clean. Will absolutely be hiring them again for future projects"

Francesca L on March 2024

Avatar for St. James Construction, LLC

St. James Construction, LLC

.
5.00(
5
)
•Approved Pro

St. James Construction, LLC

.
5.00(
5
)
•Approved Pro
Customers say: Quick response
Recommended by 100% of Angi customers
Recommended by 100% of HomeAdvisor customers
266 local quotes requested

At our company, your satisfaction is our top priority. We are committed to completing every job to the highest standards, ensuring exceptional quality and service. Discover our range of services and reach out today to book your free estimate. Let us show you the difference our dedication can make!

"Corey and his team are great to work with. He is a prompt communicator and is very organized. He also has a great attention to detail and ensures the project is perfect before claiming he is done. He is easy to work with and was able to make our ideas a reality. We have used him for several projects already and have him lined up for another. I highly recommend St. James Construction."

Chris T on January 2025

At our company, your satisfaction is our top priority. We are committed to completing every job to the highest standards, ensuring exceptional quality and service. Discover our range of services and reach out today to book your free estimate. Let us show you the difference our dedication can make!

"Corey and his team are great to work with. He is a prompt communicator and is very organized. He also has a great attention to detail and ensures the project is perfect before claiming he is done. He is easy to work with and was able to make our ideas a reality. We have used him for several projects already and have him lined up for another. I highly recommend St. James Construction."

Chris T on January 2025

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FAQs for water heater repair or service projects in Merrimack, NH

Warning signs include fluctuating water temperatures, a pilot light that repeatedly goes out, unusual noises from the tank, or complete heating failure. You might also detect a rotten egg smell, indicating a potential gas leak, or notice water that never reaches the proper temperature. If your water heater is over eight years old and displaying these symptoms, the gas valve is a likely culprit. Professional inspection is recommended, especially if gas odors are present.

Water heater gas valves are not universally interchangeable. Each valve must match your specific water heater's make, model, and specifications. Important compatibility factors include gas type (natural gas vs. propane), BTU rating, connection types, and physical dimensions. Using an incorrect valve can result in poor performance, premature failure, or dangerous gas leaks. Always consult your water heater's documentation or a professional plumber to identify the appropriate replacement valve for your unit.

The Merrimack, NH homeowners’ guide to water heater repair or services

From average costs to expert advice, get all the answers you need to get your job done.

See all articles