When a failed water heater needs replacing now
A tank that leaks from the shell cannot be fixed. The steel has rusted through, and patching it only buys hours. Shut the cold water valve on the supply pipe to the tank, switch off the breaker or the gas control, and open a hot tap upstairs to relieve pressure.
Then call. Same-day appointments are offered when available, including nights and weekends, and a plumber will ask the questions that decide the new unit: fuel, tank size and where it sits. If the leak is slow, a bucket and a towel buy time. If it is gushing, move belongings off the floor and turn off power to anything near the water.
Gas smell? Leave and call Spire at 800-887-4173 or 911 from outside before you call us.
Repair or replace
Not every dead heater needs a new tank. The table shows how we weigh it, and we will walk you through the numbers for your own unit.
| Situation | Usually better to | Why |
|---|---|---|
| Tank leaks from the shell or bottom | Replace | Rust-through cannot be sealed |
| Heater is over 10 to 12 years old and needs a major part | Replace | Repair cost approaches the cost of a new unit |
| Bad thermostat or element on a heater under 8 years old | Repair | Small part, tank is still sound |
| Rust-colored water at every hot tap | Replace in most cases | Corrosion is inside the tank |
| Relief valve drips but tank is dry and young | Repair | Valve or pressure problem, not the shell |
Tank down? Call the 24/7 line and a plumber will plan the swap with you.
Call (855) 575-2890Choosing size and fuel
Match the new tank to the household, not to the old label. A 40 gallon tank suits most one to three people. A family of four or more usually does better with 50 gallons or a unit with a high recovery rate.
Gas heats fast and costs less to run in many homes, but it needs a flue, a gas line and a safe supply of combustion air.
Electric is simple to install and has no flue, though it needs a dedicated circuit and heats more slowly.
Hybrid heat pump uses much less power and needs open space and a condensate drain.
Switching fuel adds work. Moving from electric to gas can add venting at $500 to $1,500 nationally and a gas line upgrade at $350 to $2,000. Going the other way can add an electrical circuit at $250 to $900. Our installation page explains the code side, and the tankless page covers on-demand units.
Replacement cost and what moves it
National cost guides show a 40 to 50 gallon tank installed at $600 to $3,100, and a straight swap of a 40 gallon tank at $600 to $3,000. Those are national ranges, not a quote. We give a clear price before work starts.
A water heater that fails from age is generally not covered by homeowners insurance, but sudden water damage from a burst tank sometimes is. Ask your insurer before you clean up.
Permits and cold-weather placement in Hazelwood
The City of Hazelwood contracts with St. Louis County for plumbing permits and inspections, and plumbing work requires a St. Louis County license. We pull the permit through the county when your job needs one. Ask any plumber you hire to confirm the license, because unpermitted work can cause trouble when you sell.
Hazelwood publishes a 2 degree F winter design temperature and a 30 inch frost depth. That makes an unheated garage a rough home for a tank and the pipes feeding it. After the January 2024 cold snap, when Missouri American Water reported 16 main breaks in one day, many owners moved supply lines to a warmer spot. Ask us whether yours should move too.
The International Plumbing Code (IPC) calls for a relief valve and discharge pipe on storage water heaters, and the manufacturer's installation instructions set venting and clearances. For gas units, the fuel gas code covers the gas piping, so a replacement is more than swapping tanks.
What the swap looks like
- Drain and disconnect. We shut off fuel and water, drain the old tank and disconnect the lines.
- Haul out the old tank. The tank leaves with us unless you ask to keep it.
- Set and connect the new unit. New connectors, a relief valve and discharge pipe, and an expansion tank when the code or the system calls for it.
- Test and show you. We fire or power the unit, check for leaks and show you the shutoff and the temperature setting.
We also serve Bridgeton and nearby towns on the same line.
Frequently asked questions
Yes. The line is open 24 hours a day, seven days a week. Call, tell us the fuel type and whether the tank is leaking, and shut off the cold supply. We offer same-day appointments when available.
A leaking shell means replace. Age past 10 to 12 years with a major part failing usually does too. A bad thermostat or element on a younger tank is usually a repair.
Most one to three person homes do well with 40 gallons, and larger households often need 50 gallons or more. Peak use matters more than the total number of people.
Plumbing permits for Hazelwood run through St. Louis County. We confirm what your job needs and handle the paperwork.
Yes. Removal is part of the job unless you want to keep the tank, and national guides list removal at $75 to $500 when it is priced separately.
Usually yes, but it adds work such as venting, a gas line upgrade or a new circuit. We price those separately and explain them before we start.
Questions about your situation? A licensed plumber is on the line any hour.
Call (855) 575-2890