A tank that has split open and is pouring water across the floor needs a replacement, not a parts swap, and the 24/7 line in Dedham, MA is there for that moment. Close the cold water valve above the tank, cut the power at the breaker or set a gas unit to off, and keep people and stored boxes away from the water.
Water heater replacement means a licensed plumber drains the failed unit, removes it, sets a new one with the correct valves and venting, and tests it before leaving.
Decide in the first hour: repair, replace or wait.
Not every cold shower means a new tank. The question that settles it is where the problem sits: in a replaceable part, or in the steel tank itself. Use the table below to see where your situation falls, then let the plumber confirm on site.
| Situation | Leans toward | Why. |
|---|---|---|
| Water pooling at the base of the tank | Replace | The inner shell has corroded through. |
| Failed element or igniter, tank dry | Repair | A part can be swapped. |
| Tank old, scaled and noisy, now leaking | Replace | Further repairs rarely pay off. |
| Hot water only a few minutes long | Inspect first | Could be an element or sediment. |
| Rust-colored hot water, clear cold water | Inspect first | May be the tank or the anode. |
If repair is still on the table, see water heater repair for the part-by-part checks.
When a leak means the tank must be replaced.
Many people ask whether a leaking water heater can be patched. Sometimes it can, but only when the water comes from something that bolts onto the tank: an inlet or outlet fitting, the drain valve, or the relief valve and its discharge pipe. Tighten, reseal or replace that part and the problem ends.
When the water comes from the tank body, the answer changes. The inside of the tank is steel lined with glass, and once rust breaks through, water finds the gap and the leak grows. Nothing patches it from outside.
A plumber will usually confirm by drying the unit, watching where the water forms, and checking whether the insulation jacket is soaked. Wet insulation and rust streaks down the side point to the shell. Replace the tank and ask the plumber to look at the connecting pipes and shutoff valve while the old unit is out.
Tank split open or no hot water for good? Call the 24/7 line for replacement.
Call (617) 752-0573What a same-day replacement visit involves.
- The plumber confirms the fuel, tank size and venting, and sets out the quote so you can approve it..
- Water, power and gas to the old unit are shut off and the tank is drained..
- The old heater is disconnected and carried out for disposal..
- The new heater is set, with new flexible connectors, shutoff valve and relief valve fitted as required..
- The relief valve discharge pipe, venting or electrical connection is completed and checked..
- The tank is filled, air is purged, and the unit is fired and tested before the plumber leaves..
Permit, relief valve and pan rules on a swap.
Replacing a water heater is a permitted job in Massachusetts. Mass.gov says permits are issued only to licensed plumbers, so the plumber applies through the Dedham Building Department's Plumbing/Gas Division, which takes applications through its OpenGov portal. If a contractor says no permit is needed for a full swap, ask them to explain.
The code, 248 CMR 10.14(6)(f), also requires a temperature and pressure relief valve with a full-size, non-ferrous discharge pipe that ends at a fixture or within 12 inches of the floor. Tank-type heaters need a vacuum relief valve too.
For a heater of 6 gallons or more above an occupied space, the Mass.gov safe waste pan policy calls for a pan piped to a trapped fixture or within 12 inches of the floor. On a replacement, an approved automatic shut-off device with a pan is an accepted alternative, so ask which one your quote includes.
Heat pump and hybrid water heater replacement.
A hybrid or heat pump water heater pulls heat from the surrounding air and moves it into the tank, with an electric element as backup. It needs space around it and a place for condensate to drain, and it cools the room it sits in.
We make no claims about incentives or rebates because none have been verified for Dedham, so check with your electric provider and with the manufacturer before you buy. Ask the plumber whether the closet or basement corner has the clearance and drain the unit needs.
Choosing the next heater: tank, tankless or hybrid.
Replacement is also the moment to question what you have. A like-for-like tank is the fastest swap, and it is usually what an emergency calls for. A switch to tankless or to a different fuel takes more planning, because the gas line, venting or electrical service may need work first.
- Same fuel, same size: fastest in an emergency, because connections already exist.
- Larger or smaller tank: may require new venting or a different footprint.
- Gas to electric or the reverse: needs a new circuit or gas line, and a permit.
- Tankless: see tankless water heater service before you commit.
If you have time to plan, water heater installation covers fuel changes in more detail.
Hard water and the heater you are about to buy.
The Dedham-Westwood Water District reported average hardness near 6.0 grains per gallon in 2025, so scale will settle in any heater you install here. Ask the plumber to fit shutoff and drain valves you can reach and to explain how to flush the tank. A drain valve that is blocked by sediment or hidden behind a wall makes later maintenance harder, so decide on placement before the tank goes in.
What a replacement quote should list.
A clear price before work starts should itemize the main cost drivers, so you can compare quotes fairly:
- The heater itself, by fuel, tank size and recovery rate.
- Venting, gas line or electrical changes if the new unit differs from the old.
- Code items: relief valve, discharge pipe, expansion tank and safe waste pan or shut-off device.
- Permit and disposal of the old tank.
- After-hours or same-day timing, and any access problems such as stairs.
Homeowner policies generally cover sudden and accidental damage rather than wear and tear, so ask your insurer how it treats a burst tank and the water damage around it. Want your real number? Call (617) 752-0573.
While the old tank sits dead.
- Close the cold supply valve above the tank.
- Turn off the breaker, or set the gas control to off or pilot if reachable.
- Move anything stored near the base out of the water.
- Take photos of the tank label, the leak and any damage.
- Keep children and pets out of the wet area, especially near outlets.
- If you smell gas, leave the building, call 911 from outside, and call your gas utility.
Frequently asked questions.
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Yes. Dispatch runs 24/7, and a licensed plumber can assess a failed tank after hours. Whether the new unit is installed that night depends on stock and access, so ask the dispatcher what is realistic. No arrival time is promised, but you will get an honest estimate on the call.
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Leaks from fittings and valves can often be repaired. Water from the base or sides of the tank, a soaked jacket and rust streaks usually mean the shell has failed. A plumber can confirm after drying the tank and checking every connection.
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Often, when a same-day appointment is available and the replacement matches your current fuel and venting. Changes in fuel, tank size or location take longer because they need extra parts and sometimes extra permitting.
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Yes. Mass.gov says permits are issued only to licensed plumbers, and in Dedham they go through the Building Department's Plumbing/Gas Division. Your plumber handles the application.
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It can be, if the location has space, airflow and a condensate drain. The plumber can check the spot. Because incentives are not verified for Dedham, confirm any rebate directly with your provider before relying on it.
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Shut off the supply, switch off power, then remove standing water with a mop or wet vacuum once the outlets are dead. Dry the area quickly to limit mold, and photograph the damage for your insurer.
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About three in ten Dedham households rent. Notify your landlord in writing right away, since the landlord usually arranges the replacement. A plumber can speak with the property manager to set the visit.
Codes, standards and sources.
Plumbing work in Massachusetts is governed by 248 CMR 10.00, the Uniform State Plumbing Code, and plumbers are licensed by the Board of State Examiners of Plumbers and Gas Fitters. You can read the state's consumer fact sheet on plumbers and gas fitters before you hire anyone.
Local facts on this page come from the Dedham-Westwood Water District, the Town of Dedham, the other towns named and Mass.gov, and were checked in October 2026. Where a fact could not be confirmed, the page says to ask the utility or the town.