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Water heater installers and replacers in Merrimack

Avatar for JMS Plumbing and Heating, LLC
JMS Plumbing and Heating, LLC
11 Jakes Lane
4.66(
28
)
Approved Pro
JMS Plumbing and Heating, LLC
11 Jakes Lane
4.66(
28
)
Approved Pro
Customers say: Quick response
25 years of experience
Free onsite estimate

Whether you need a simple faucet installation or complete waterline replacement, we offer a wide range of residential and commercial plumbing services to meet your needs. We continually strive to exceed expectations by ensuring that each client receives the very best service. Individualized Plumbing Options We strive to exceed expectations by ensuring all your plumbing work is completed to the highest standards. We will provide you with a free consultation to explain all of your available options so you can choose the scope or work that?s right for your home or business.

"great service and 5 star results "

mikes cottages at hampton beach n.h. v on January 2025

Whether you need a simple faucet installation or complete waterline replacement, we offer a wide range of residential and commercial plumbing services to meet your needs. We continually strive to exceed expectations by ensuring that each client receives the very best service. Individualized Plumbing Options We strive to exceed expectations by ensuring all your plumbing work is completed to the highest standards. We will provide you with a free consultation to explain all of your available options so you can choose the scope or work that?s right for your home or business.

"great service and 5 star results "

mikes cottages at hampton beach n.h. v on January 2025


Avatar for Flow Pro Plumbing and Drain Cleaning LLC
Flow Pro Plumbing and Drain Cleaning LLC
53 Delaware Ave
5.00(
2
)
Approved Pro
Flow Pro Plumbing and Drain Cleaning LLC
53 Delaware Ave
5.00(
2
)
Approved Pro
Customers say: Quick response
1 years of experience
Emergency services offered

We are a local, family-owned business that provides quality plumbing and drain cleaning services to Manchester and surrounding areas. We have over 6 years of experience servicing New Hampshire for all your plumbing needs.

"Service was fast he cleaned when he was done I was so happy I had him install a kitchen faucet that looks great and he gave me w fair price if we have any problems in the future we will use flow pro again"

Eugene T on September 2024

We are a local, family-owned business that provides quality plumbing and drain cleaning services to Manchester and surrounding areas. We have over 6 years of experience servicing New Hampshire for all your plumbing needs.

"Service was fast he cleaned when he was done I was so happy I had him install a kitchen faucet that looks great and he gave me w fair price if we have any problems in the future we will use flow pro again"

Eugene T on September 2024


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
54 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!

"they came out and gave me a very fair estimate. they told me approximately when i can expect the work to be done. it was done even sooner than that. The two installers showed up. they were professional, on time, called ahead, left everything clean, took everything away with him, did it right the first time. definitely will use them again"

Jeffrey B on June 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!

"they came out and gave me a very fair estimate. they told me approximately when i can expect the work to be done. it was done even sooner than that. The two installers showed up. they were professional, on time, called ahead, left everything clean, took everything away with him, did it right the first time. definitely will use them again"

Jeffrey B on June 2025


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 Rowell's Services, LLC
Rowell's Services, LLC
359 Tilton Road
4.77(
65
)
Approved Pro
Rowell's Services, LLC
359 Tilton Road
4.77(
65
)
Approved Pro
Customers say: Quick response
Recommended by 98% of Angi customers
Recommended by 98% of HomeAdvisor customers
44 local quotes requested

Rowell's Services was founded in 1983 by Dickie and Debbie Rowell. We remain a family-owned and operated business, committed to providing excellent, efficient services within the heating, cooling, electrical, plumbing, septic and drain cleaning industry. We proudly serve all of New Hampshire. We pride ourselves in offering emergency service, and have all the equipment necessary to handle your job from start to finish! Rowell's Services is your preferred home services professional.

"Great people to work with."

Frank M on January 2023

Rowell's Services was founded in 1983 by Dickie and Debbie Rowell. We remain a family-owned and operated business, committed to providing excellent, efficient services within the heating, cooling, electrical, plumbing, septic and drain cleaning industry. We proudly serve all of New Hampshire. We pride ourselves in offering emergency service, and have all the equipment necessary to handle your job from start to finish! Rowell's Services is your preferred home services professional.

"Great people to work with."

Frank M on January 2023


Avatar for Danerik Mechanical LLC
Danerik Mechanical LLC
325 Bunker Hill Rd
4.96(
12
)
Approved Pro
Danerik Mechanical LLC
325 Bunker Hill Rd
4.96(
12
)
Approved Pro
Super Service Award
Customers say: Quality work
Recommended by 91% of Angi customers
Recommended by 91% of HomeAdvisor customers
25 local quotes requested

Danerik Mechanical LLC we pride ourselves on being the best PWC company in the area. We've built an excellent reputation for customer satisfaction by providing quick estimates, a great attention to detail, and competitive pricing. Being a screened and approved professional gives you the peace of mind you need to allow us to give your home the attention it deserves. Call us today and let's get started!

"Awesome results. Very professional and work was completed as expected."

James G on December 2024

Danerik Mechanical LLC we pride ourselves on being the best PWC company in the area. We've built an excellent reputation for customer satisfaction by providing quick estimates, a great attention to detail, and competitive pricing. Being a screened and approved professional gives you the peace of mind you need to allow us to give your home the attention it deserves. Call us today and let's get started!

"Awesome results. Very professional and work was completed as expected."

James G on December 2024


Avatar for Action Plumbing Heating And Air
Action Plumbing Heating And Air
75 South Main Street
4.91(
81
)
Approved Pro
Action Plumbing Heating And Air
75 South Main Street
4.91(
81
)
Approved Pro
Customers say: Quality work
Recommended by 98% of Angi customers
Recommended by 98% of HomeAdvisor customers
37 local quotes requested

Action Plumbing, Heating, and Air provides prompt and reliable services to homeowners and businesses. We are fully licensed, bonded, and insured and able to repair or replace any plumbing or heating fixture inside or outside of your home or business. We stand behind our products and services by installing only quality materials and hiring only state licensed plumbers. At Action, we pride ourselves on practicing the highest standards in the business to ensure our customers are provided the best service possible. Take Action against your plumbing or heating problems and call Action! (833) 732-2288

"Dave was quick to respond. Very pleasant and explained everything clearly. Took his time to make sure we were happy with the work."

Richard E on August 2024

Action Plumbing, Heating, and Air provides prompt and reliable services to homeowners and businesses. We are fully licensed, bonded, and insured and able to repair or replace any plumbing or heating fixture inside or outside of your home or business. We stand behind our products and services by installing only quality materials and hiring only state licensed plumbers. At Action, we pride ourselves on practicing the highest standards in the business to ensure our customers are provided the best service possible. Take Action against your plumbing or heating problems and call Action! (833) 732-2288

"Dave was quick to respond. Very pleasant and explained everything clearly. Took his time to make sure we were happy with the work."

Richard E on August 2024


Avatar for Derry Plumbing & Heating
Derry Plumbing & Heating
41 Birch St
4.50(
30
)
Approved Pro
Derry Plumbing & Heating
41 Birch St
4.50(
30
)
Approved Pro
Customers say: Quality work
48 local quotes requested
36 years of experience

If you�re familiar with plumbing, you know that doing it right takes just the right recipe: two parts job knowledge and three parts skill. At Londonderry Plumbing and Heating, we provide everything you need to secure the perfect plumbing solution, a mixture that will do you right, just like home cooking! No job is too small or too challenging for our dedicated professionals! Londonderry Plumbing and Heating can tackle your most challenging plumbing problems and do so at affordable rates. If you are looking for a plumber who is highly qualified, quick to respond and a pleasure to do business with, give us a call. We look forward to adding you to our list of satisfied customers!

"Great service! Emergency service and done within the day!"

Bonnie S on May 2025

If you�re familiar with plumbing, you know that doing it right takes just the right recipe: two parts job knowledge and three parts skill. At Londonderry Plumbing and Heating, we provide everything you need to secure the perfect plumbing solution, a mixture that will do you right, just like home cooking! No job is too small or too challenging for our dedicated professionals! Londonderry Plumbing and Heating can tackle your most challenging plumbing problems and do so at affordable rates. If you are looking for a plumber who is highly qualified, quick to respond and a pleasure to do business with, give us a call. We look forward to adding you to our list of satisfied customers!

"Great service! Emergency service and done within the day!"

Bonnie S on May 2025


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
976 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
217 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

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FAQs for water heater installation and replacement projects in Merrimack, NH

You'll need an expansion tank if your home has a closed water system, which is standard in newer homes or those with backflow preventers or pressure regulators. Expanding hot water has nowhere to go in closed systems, creating potentially damaging pressure. The expansion tank provides space for this expanded water, protecting your plumbing system and water heater from premature failure. Many local building codes now require expansion tanks, and some water heater warranties may be voided without one.

For a standard 50-gallon water heater, a two-gallon expansion tank is sufficient. This sizing assumes normal household water pressure between 40 and 60 psi. If your home has higher water pressure (60 to 80 psi), consider upgrading to a slightly larger tank for added protection. The expansion tank's purpose is to accommodate the increased volume that occurs when cold water heats up, which is proportional to your water heater's capacity.

Watch for signs like dripping water around the tank, fluctuating water pressure throughout your home, or unusual noises in your plumbing system. A properly functioning expansion tank should feel light when tapped on the bottom—if it feels heavy or waterlogged, the internal bladder has likely failed. Other indicators include frequent triggering of your temperature and pressure relief valve, visible corrosion on the tank, or unexplained increases in your water bill, suggesting hidden leaks.

Most expansion tanks have a service life of five to 10 years, though some may last up to 12 years or more with proper maintenance. Factors affecting lifespan include water quality, system pressure, installation quality, and tank construction. Hard water areas often see shorter lifespans due to mineral buildup. Regular maintenance checks can help identify potential issues before complete failure. When your water heater is due for replacement, it's wise to replace the expansion tank simultaneously, even if it hasn't failed yet.

A 30-gallon water heater needs an expansion tank if your home has a closed plumbing system. The need for an expansion tank is determined by your plumbing system type rather than water heater size. Even smaller water heaters create thermal expansion when heating water. If your home has a backflow preventer, pressure regulator, or check valve on the main water line, you have a closed system that requires an expansion tank. Check your local plumbing codes, as many jurisdictions now mandate expansion tanks regardless of water heater size.

The Merrimack, NH homeowners’ guide to water heater installations and replacements
From average costs to expert advice, get all the answers you need to get your job done.
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