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Find Tankless water heater installers in Mercer Island

Avatar for Stream Water Heaters
Stream Water Heaters
5.0(
50
)

Serving Mercer Island, WA and surrounding areas

Approved

In business since 2021

Free estimates

Emergency services offered

"My water heater tank stopped working so I decided to convert to a tankless system. Chad and George were who I worked with. I had a great experience with both of them. I was very pleased with their knowledge, work, communication and help. I would highly recommend them to other house owners."
A 20-Year-old gas WH.
A 20-Year-old gas WH.
Preventative Gas Repl.
Preventative Gas Repl.
Non-Condensing Tankless W

+1

Response time4 hrs
Response rate100%
Recommended by12%of homeowners
Avatar for Stream Water Heaters
Stream Water Heaters
5.0(
51
)

Serving Mercer Island, WA and surrounding areas

Approved

Super Service Award Winner

In business since 2021

Free estimates

Emergency services offered

"My water heater tank stopped working so I decided to convert to a tankless system. Chad and George were who I worked with. I had a great experience with both of them. I was very pleased with their knowledge, work, communication and help. I would highly recommend them to other house owners."
New
New 3
New 2
New Setup 2
New setup

+8

Response time5 hrs
Response rate99%
6 neighbors recently requested a quote
Avatar for Seatown Electric Plumbing Heating & Air
Seatown Electric Plumbing Heating & Air
4.8(
1,392
)

Serving Mercer Island, WA and surrounding areas

Approved (Corporate)

In business since 2013

Emergency services offered

Warranties offered

"The Seatown team did a great job. I got quotes from 3 different recommended plumbing services, but the Seatown guys were the only ones who recognized we would need to upgrade our gas meter. They did a great job explaining how to get this scheduled with PSE. The estimate Seatown gave was on par with some of the other plumbers, so we went with them. They sent 2 service people to come and install the tankless and the guys were just excellent. I expressed concern about mounting the water heater on the beams in our basement because Our house is so old, so they came up with a better solution. They built a small wall frame to mount the water heater. No extra cost. When they found there was no outlet wired near the heater they were able to get an electrician from Seatown to come out and wire one up while they worked on the water heater install. Seatown aldo had a good scheduling method, sent text reminders the day they were coming to do the work with a photo of the person who was coming and a short set of info about the person. It was a nice touch, and a thoughtful safety measure. They did a great job with the install which took several hours. I’d definitely hire them again."
Generator Repair
Additional Photos
Additional Photos
Electrical Panel Repair
Additional Photos

+44

105 neighbors recently requested a quote
Recommended by94%of homeowners
Avatar for Day & Nite Plumbing & Heating, Inc.
Day & Nite Plumbing & Heating, Inc.
4.3(
225
)

Serving Mercer Island, WA and surrounding areas

Approved

In business since 1954

Emergency services offered

Warranties offered

"Rob came out to review our existing system and helped us figure out what kind and brand of heat pump would work best with our system. He was very patient and informative, and answered all our questions without any pressure or up-sells (we had quotes from five providers). We signed the contract and payed our deposit in June 2021, but unfortunately global supply chain issues delayed the parts being received. Day & Nite were communicative of the issue and offered several alternatives, including a refund of the deposit. We opted to wait for the parts. It took four months, but the techs (lead by Jeff B) were fantastic and very accommodating in how we wanted piping and wiring routed. We are very pleased with how it's turned out and loved working with a local (and family owned!) company! Our gas water heater is due for replacement soon, and we'll be coming back to Day & Nite for that!"
Outdoor Ductless Unit
Indoor Ductless Unit
Outdoor Ductless lineset and Unit
Pump System
Response time2 days
16 neighbors recently requested a quote
Recommended by82%of homeowners
Avatar for Drain Pro Plumbing Inc
Drain Pro Plumbing Inc
4.8(
603
)

Serving Mercer Island, WA and surrounding areas

Approved

In business since 2009

Free estimates

Emergency services offered

"Great. I received 3 bids and Drain Pro's was the most competitive and thorough. We scheduled a date, and installation was done in a day. They removed my old electric water heater and were tidy and very professional. I paid by check as they left. Now I will have to install an electrical outlet next to the heater but meanwhile, it's on an extension cord... Looking forward to 24-hour hot water, and a lower electric bill!"
Water service
Split water meter
Water meter installation
Water heater installation
Broken p-trap and pop assembly

+18

Response time1 day
Recommended by97%of homeowners
Avatar for Northwest Hydrojetting, LLC
Northwest Hydrojetting, LLC
5.0(
14
)

Serving Mercer Island, WA and surrounding areas

Approved

Super Service Award Winner

In business since 2018

Free estimates

Emergency services offered

"I have used this plumber for over 4 years now - they respond immediately to any concern, are the most honest and fair people out there! Anything from simple drain clear, or water heater install, to a side sewer and complete DADU plumbing installation…they do it all, and with great communication! I pass their name and number to anyone who is looking for an honest and reliable plumber!"
Camera inspection
Camera inspection
Repairs
Remodels
Remodels

+11

Response time4 hrs
45 neighbors recently requested a quote
Recommended by7%of homeowners
Avatar for Pipers Drain Repair LLC
Pipers Drain Repair LLC
4.8(
14
)

Serving Mercer Island, WA and surrounding areas

Approved

In business since 2025

Free estimates

Emergency services offered

Pipers Drain Repair is a trusted provider of professional plumbing company services dedicated to keeping residential and commercial plumbing systems flowing efficiently. With a commitment to quality workmanship, fast response times, and exceptional customer service, Pipers Drain Repair specializes in diagnosing and resolving a wide range of plumbing issues, from leaking water line repairs to full house repipes. Using advanced equipment and proven techniques, the company delivers reliable, long-lasting solutions that help prevent costly future problems. Pipers Drain Repair takes pride in offering honest assessments, transparent pricing, and customized services tailored to each customer’s needs. Whether handling routine maintenance, drain inspections, hydro jetting, or complex repairs, the team is focused on delivering dependable results with minimal disruption. Known for professionalism, integrity, and attention to detail,

Liner Install
Liner Install
sewer camera inspection
Sink Drain Repair
Sink Drain Repair

+11

1 neighbors recently requested a quote
Avatar for Rescue Rooter Seattle
Rescue Rooter Seattle
4.5(
132
)

Serving Mercer Island, WA and surrounding areas

Approved (Corporate)

Super Service Award Winner

In business since 1976

Free estimates

Emergency services offered

"Bryce and Eva were fantastic. I had a pipe rupture. I was in a panic. They walked me through the most effective way to shut off the water. They didnâ t provide the service to repair everything the next day. I asked if he could repair a toilet while he was here. He graciously took care of that as well. I could not ask for more."
Clogged Drain
Recommended by88%of homeowners
Avatar for Harts Plumbers, Electricians, & HVAC Technicians
Harts Plumbers, Electricians, & HVAC Technicians
4.6(
1,222
)

Serving Mercer Island, WA and surrounding areas

Approved

Super Service Award Winner

In business since 2013

Emergency services offered

Warranties offered

"The quality was great and the plumber was incredibly friendly, easy to work with. My only concern was I was never provided pictures of the tub surround as discussed and not given the option to chose, just got what was picked out for me. This was a pretty big 4-day project, re-pipe of water, sewer lines, new tankless water heater, new tub and 2 new toilets. I do not love that 2 different toilets were installed. Again, I was not consulted about the style of toilets."
Pipe llining
Pipe relining
Pipe relining
Camera inspections
Response time50 mins
Response rate100%
20 neighbors recently requested a quote
...
Showing 1-10 of 125

The Mercer Island, WA homeowners’ guide to tankless water heater installations

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