Cohasset · Water Heaters
No hot water, a leaking tank, or a heater that's near the end of its life in a Cohasset home? Check for gas and CO safety first, then call to reach an independent local plumber.
Cohasset, Massachusetts
Most water heater calls start with a cold shower, but in Cohasset the first thing to rule out is air quality. Gas service in town comes from National Grid, and a gas or oil-fired heater that isn't venting properly can push carbon monoxide into the house. The Cohasset Fire Department posts the carbon monoxide alarm requirements homes must meet, so make sure your alarms work before anyone starts troubleshooting the heater.
Age is the next clue. Census estimates put the median Cohasset home's construction year at 1968, and many older basements have seen several heaters come and go, each fitted to whatever venting, gas line, or electrical circuit was already there. When a tank fails, the replacement may need updates to those connections, not just a new heater dropped in place.
Call or send a request and you'll be connected with an independent plumber who repairs and replaces water heaters in Cohasset. We're a referral service; the plumber quotes and does the work.
Moisture at the base often means the tank itself has corroded through, which can't be patched. A leak at a fitting or valve on top is usually repairable.
Sediment built up in the bottom of a tank, or a failed element in an electric unit, shrinks how much hot water you get.
Noise from the tank as it heats is often sediment. Flushing can help on a younger heater; on an old one it may signal replacement time.
Black marks near the burner or a sounding carbon monoxide alarm point to a venting or combustion problem. Leave the house and call 911 from outside.
Local knowledge
Local rules and utilities to know before you repair or replace a Cohasset water heater.
CO Alarms
The Cohasset Fire Department page, as archived in February 2026, lists carbon monoxide alarm requirements and smoke alarm information. A fuel-burning water heater is one of the appliances those alarms protect against, so test them whenever the heater is serviced.
Source: Cohasset Fire Department (archived page, February 2026)
National Grid Service
State utility lists show National Grid as Cohasset's gas company (Boston Gas) and its electric company (Massachusetts Electric). That makes National Grid the call for a gas smell outside or a meter problem, and its programs relevant whether your heater runs on gas or electricity.
Source: Mass.gov utility listings
Heat Pump Rate
Cohasset Community Electricity, the town's aggregation program, notes that from November 1, 2025 most National Grid customers with heat pumps get a discounted heat pump delivery rate. If you're weighing a heat pump water heater, ask National Grid and Mass Save how that rate and their rebates apply to your home.
Source: Cohasset Community Electricity
Right now
Safety comes first, then limiting water damage.
If you smell gas or a carbon monoxide alarm sounds, get everyone out and call 911 or National Grid from outside. On the way out, skip the light switches, and leave any pilot or burner reset for whoever answers the call.
Most tanks have a shutoff on the cold line coming in at the top. Turning it off keeps the leaking tank from taking on more water.
If water has reached an electric heater's wiring or a nearby outlet, stay out of the puddle and leave the electrical side to the plumber or an electrician.
Snap a photo of the heater's rating plate showing the fuel type, size, and manufacture date. It helps the plumber bring the right parts or price a replacement.
What to expect
The plumber will check the burner or elements, controls, venting, and the relief valve, then tell you whether a repair makes sense or the tank is done. On older Cohasset homes, they'll also look at whether the existing vent, gas line, or circuit can carry a new unit, since replacements are often a different size or type than the original.
Replacing a water heater usually needs a permit. Cohasset's Building & Inspections office handles plumbing and gas inspections, and its page archived in February 2026 said permits are filed online and inspections are booked by contacting the department. Your plumber should file it and be there for the inspection.
If your basement is near the harbor or cove, where the town has mapped coastal flooding pathways, ask whether the new heater should sit on a raised platform so storm water can't reach the burner or controls.
Hire smart
Plumbing and gas fitting in Massachusetts require a license from the Board of State Examiners of Plumbers and Gas Fitters, and most plumbing work needs a permit from the town's plumbing inspector.
Gas water heaters need a plumber or gas fitter with a Massachusetts license. Look up the number on the state's occupational license search.
A replacement should go through Cohasset's Building & Inspections office; ask the plumber to confirm it in writing.
Ask the plumber to explain which types fit your space, venting, and household use, and to check Mass Save for current incentives.
Make sure removal and disposal of the old heater are part of the written estimate.
Costs
A repair price depends on the part and how quickly it can be found. A replacement depends on the type and size of heater, whether the venting, gas line, or wiring needs to be updated, how hard the basement is to reach, and whether the unit needs to be raised in a flood-prone spot.
Get a written estimate that lists the heater, labor, permit, disposal, and any venting or electrical changes. If you're considering a heat pump unit, ask about Mass Save incentives and the National Grid heat pump rate before you compare totals.
More help in Cohasset
Every page below is written for Cohasset homes. Or start from the Cohasset plumbing guide.
Learning Center
A short list of the right questions tells you more about a plumber than any ad. Use these on the phone, during the site visit, and before you sign off on an estimate.
Read the guide
Massachusetts has some of the clearest plumbing rules in the country. Here is how to use them to pick a plumber with confidence, whether the job is a dripping shutoff or a full repipe.
Read the guideQuestions
Still not sure? Send a short request and a local pro can answer the specifics.
The Cohasset Fire Department posts the carbon monoxide alarm requirements that apply to homes, so start there. If your heater burns gas or oil, ask the fire department or your plumber where alarms should go for your floor plan.
Get out of the house before you make any call, then reach 911 or National Grid from the yard or a neighbor's. National Grid supplies gas in Cohasset. Once the area is declared safe, a plumber can inspect the heater and its connections.
It can be, if there's enough space and air around it and a suitable circuit. The town's electricity aggregation program notes a discounted National Grid delivery rate for most heat pump customers starting November 1, 2025; ask National Grid whether it covers your setup, and check Mass Save for rebates.
Yes, in most cases. Building & Inspections handles plumbing and gas permits and inspections in Cohasset, and permits are filed online. The plumber you hire should file the permit and arrange the inspection.
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