
Tankless Water Heaters in Gardiner, Maine
Endless Hot Water · Space-Saving Design · 20+ Year Lifespan
- Google reviews
- Licensed & insured
- Since 2019
Efficiency Maine Registered Vendor- 100% Satisfaction Guarantee
Current offers & financing
See all coupons →Financing available
Finance up to 100% of your project with low monthly payments through our lending partners. Quick approval, no prepayment penalty.
Tankless Water Heaters for Gardiner Homeowners

Aces Highlands handles tankless water heaters for homeowners throughout Gardiner. We work out of 508 Riverside St Unit 1 in Portland, a short drive into Kennebec County, so response times stay quick and every job benefits from knowing the local housing stock and code requirements.
Tankless water heaters heat water on demand, providing endless hot water while saving space and energy. Aces Highlands installs propane and electric tankless systems properly sized for your household needs.
A tankless water heater heats water only when you need it, eliminating the standby energy loss of keeping a tank of water hot around the clock. This can reduce your water heating costs by 24-34% depending on your usage.
We install tankless units from trusted brands and ensure proper gas line sizing, venting, and water flow for optimal performance. Electric tankless models may require an electrical panel upgrade to support the higher amperage draw. Not every home is a good candidate for tankless — we evaluate your situation honestly and recommend the best option.
Tankless water heaters last 20+ years with proper maintenance, compared to 10-12 years for tank models. While the upfront cost is higher, the longer lifespan and energy savings make tankless a smart long-term investment for many homeowners. We offer financing to help spread the cost over time.
Why Gardiner Calls Aces Highlands
- Based just outside Gardiner and out on Kennebec County calls every day
- Honest diagnostics and transparent pricing — no upselling
- Scheduling that moves quickly, because a home without heat or water cannot wait
- Licensed and insured; Google reviewers back up the work
Gardiner Homes and What They Need
Gardiner's median home was built in 1944, with 47 percent of housing dating before 1940 and two-thirds before 1960 -- among the oldest housing stock of any Kennebec County town Aces serves. Much of it sits inside the National Register-listed downtown historic district, about 7 acres and 47 buildings along Water Street, Cobbossee Stream and the Kennebec riverbank. Exterior work in that district can draw added review, so a heat pump installation near downtown often starts with a conversation about where the outdoor unit can actually go.
Water Supply and Drains in Gardiner
Gardiner draws its public water from the Gardiner Water District's gravel-packed wells, while the city runs its own wastewater treatment plant in South Gardiner. The city sits right where the Kennebec River meets Cobbossee Stream, which drops about 130 feet over falls on its way through downtown -- a dramatic bit of geography that also means older sections of the sewer system have had a long time to age. A camera inspection ahead of any sewer line repair is worth doing on Gardiner's older streets.

Getting to Know Gardiner
Gardiner traces back to 1754, when Boston physician and drug merchant Dr. Silvester Gardiner began developing more than 100,000 acres at the head of navigation on the Kennebec River. The city later built an economy around exporting river ice, packed in sawdust and shipped as far as the tropics, alongside a paper industry that boomed from the 1860s into the 1920s.
Gardiner's entire downtown was added to the National Register of Historic Places in 1980, and the poet Edwin Arlington Robinson, who won three Pulitzer Prizes, grew up here and is still remembered locally. That historic downtown, with its ice-and-paper-era brick blocks, is a big part of why Gardiner's housing stock runs as old as it does.
Local & Independent — Not a Franchise
Aces Highlands answers to Gardiner homeowners directly, not a franchise office somewhere else in the country. Our technicians are not commissioned salespeople and nobody here is required to upsell you anything. We do the work you called us for, do it right, and earn the next call. That is the whole business model.
How a Tankless Water Heater Works
- Flow sensor — detects water flow and triggers ignition
- Burner — fires on demand, no standby tank
- Heat exchanger — heats the water as it passes through
- Hot water out — instantly, only when it's needed
- Compact — mounts on the wall, saves floor space
Homeowner Guide
Tankless Water Heaters: Sizing by Flow Rate, Not Gallons
A tankless water heater is sized completely differently from a tank, and misunderstanding that is the most common reason a homeowner ends up disappointed with one.
Read the Full GuideMore Water Heaters
Tankless Water Heaters is part of our full water heaters lineup. Explore the details or browse everything we offer in Gardiner.
Tankless Water Heaters DetailsAll Services in GardinerService Info
Codes & Permits for Tankless Water Heaters in Gardiner
In Gardiner, plumbing permits come from the Local Plumbing Inspector at the City of Gardiner Code Enforcement Office (Gardiner City Hall, 6 Church Street, Gardiner, ME 04345, (207) 582-6892). With 5,961 residents, Gardiner is required to enforce the Maine Uniform Building and Energy Code (MUBEC). The Gardiner Historic District — about 7 acres and 47 buildings along Water Street, Cobbossee Stream, and the Kennebec riverbank — was listed on the National Register of Historic Places on May 6, 1980, which can affect exterior work (including HVAC unit placement) on those buildings.
- A propane or natural gas-fired water heater installation or connection requires a Maine Fuel Board Propane and Natural Gas Technician license. mainelegislature.org
- Maine's adopted plumbing code (2021 Uniform Plumbing Code) requires every water heater's potable-water connections and temperature/pressure relief valve to meet UPC installation requirements, including a proper gravity discharge line. up.codes
- Replacing or installing a water heater is plumbing work that falls under the town's Local Plumbing Inspector permitting and inspection process. mainelegislature.org
- Every Maine municipality must annually appoint at least one Local Plumbing Inspector (LPI), who does not have to live in that town, to issue plumbing permits and enforce the state's plumbing rules and Subsurface Wastewater Disposal (septic) rules locally. mainelegislature.org
How Aces Highlands Handles Tankless Water Heaters in Gardiner
- Gardiner Water District covers most of Gardiner (gravel-packed wells) — homes still on a private well get the well and pressure tank looked at as part of the same visit.
- Summit Natural Gas of Maine reaches parts of Gardiner, so a gas water heater is an option on those streets; propane, electric and heat-pump models work anywhere in town.
- The swap is permitted through the City of Gardiner Code Enforcement Office, the relief valve gets a proper gravity discharge line, and any gas connection is made under our Maine Fuel Board license.
Gardiner's municipal building on Church Street, seat of the city government.
Street View © Google
Why homeowners choose Aces Highlands
We show up when we say
We show up on time, as promised, and complete the work with clean professionalism.
Pricing upfront, before work starts
Honest diagnostics and a clear price before any work begins — no surprises on the invoice.
Done right the first time
HVAC, plumbing and electrical done right the first time — backed by our workmanship guarantee and 100% satisfaction guarantee.
Locally owned in Portland, Maine · Serving Greater Portland and Southern Maine since 2019
What Water Heaters customers say
Nichole A
a year ago
Highly recommend! Cannot thank them enough for fixing my water heater. Elijah is very reliable and communicative. No hassle, no phone tag, transparent with cost and quick to repair the issue. I know who to call if I need help again!
Ruth Kirkwood
3 months ago
This company is excellent. They quickly and efficiently repaired the kitchen faucet that was loose.
Susan Donegan
3 months ago
We have called Samuel for our electrical needs over the last few years and have always been impressed with professional and courteous attitude — installing extra outlets, installing new lights and ceiling fans, our whole house generator, charger for the electric car, even the hot tub!!! His price was fair, and never disappointed when work was completed.
Amanda R
2 months ago
I've had an excellent experience working with them for both electrical and HVAC work as I remodel my 1785 home. I highly recommend them.
Malina Foss
3 months ago
I can not recommend Sam and his team enough!! In a world of slow response times and cut corners they went above and beyond in every area, installing a new electrical panel for me. Their attention to detail and love of their craft truly sets them apart from the rest!
Steve Robertson
3 months ago
Where to begin? These guys hooked up a sauna for me and did an amazing job, it was not a small job. Projects big or small, these guys are my go to. Responsive, reasonably priced, and professional. In a world where it is tough to get good service, I'm thrilled to have these guys in my phone.
Tankless Water Heaters FAQs
Does a tankless water heater really provide endless hot water?
Yes, within its flow capacity. A properly sized unit will run a shower indefinitely without going cold. The limit is simultaneous use — run three showers and a dishwasher at once and you can exceed its flow rate. That is why honest sizing for your household matters more than the brand.
How much does tankless water heater installation cost?
Nationally, installed costs typically run $2,500-$5,500 depending on fuel type, venting, and whether gas lines need upsizing — higher than a tank swap. The offset is a 20+ year lifespan and lower operating costs. We quote your exact price in writing before any work begins.
How long do tankless water heaters last?
Twenty years or more with annual descaling and basic care — roughly twice the life of a tank water heater. The heat exchanger is the key component, and keeping it free of scale is what gets you the full lifespan.
Does Maine’s cold groundwater affect tankless performance?
Yes, and it is the most important local factor. Winter inlet water in Maine can be 30+ degrees colder than in southern states, which reduces a unit’s effective flow rate. We size for Maine winter conditions so your system performs in January, not just on paper.
Will you talk me out of tankless if it is wrong for my home?
Yes — and we do it regularly. As a local company with no sales commissions, we have no reason to push the more expensive option. If your usage, fuel situation, or budget points to a quality tank heater instead, that is exactly what we will recommend.
More Services in Gardiner
Aces Highlands handles HVAC, plumbing, and electrical for Gardiner homeowners. Here is more of what we do nearby.
Water Heater Repair in Gardiner
Water Heater Repair in GardinerPanel Upgrades in Gardiner
Panel Upgrades in GardinerWiring & Rewiring in Gardiner
Wiring & Rewiring in GardinerOutlet & Switch Installation in Gardiner
Outlet & Switch Installation in GardinerLighting Installation in Gardiner
Lighting Installation in GardinerEV Charger Installation in Gardiner
EV Charger Installation in GardinerNeed Tankless Water Heaters in Gardiner?
Call our Gardiner team or get a free quote. We will get you scheduled and take care of it right the first time.
More Ways We Can Help
Google ReviewsGuides & Tips
8For more background, read our guides, including…
Company
8Get to know Aces Highlands through…
Services
39Homeowners often pair this with our other offerings, including…
Service Areas
48We also serve homeowners in…
Get a Quote in Gardiner
Request Service
Fill out the form below to request an estimate or schedule service.
“*” indicates required fields
Need it today?Call (207) 670-8616











