A tank that has burst, rusted through or stopped heating for good is an emergency replacement call. Our 24/7 line is answered around the clock, and we book same-day appointments when available for Maryland Heights homes.
While you wait, shut the cold water valve above the tank, switch off the breaker or set the gas control to off, and open a hot tap upstairs so the pipes drain slowly. If water is on the floor, move anything stored nearby and keep people away from wet outlets. If you smell gas, leave and call Spire at (314) 621-6960 or 911 before you call us.
Once the dispatcher has your tank size, fuel type and location, we can talk through the replacement before anyone arrives. That shortens the visit, because the plumber brings the right unit and fittings.
A flooded tank: the first hour
A failed tank is messy but manageable if the first few steps are done correctly.
Do these before the plumber arrives
- Close the cold inlet valve, or the main shutoff if that valve will not turn.
- Turn off power at the breaker. An electric element burns out within minutes if the tank runs dry.
- Set a gas control to off and ventilate if the closet is closed in.
- Run a hose from the drain valve to a floor drain only if the water is cool. Hot water scalds.
- Photograph the tank, the label and the water damage for your insurance claim.
Sudden tank failure is sometimes covered by homeowner policies as water damage, but wear and corrosion usually are not. Ask your insurer which applies to you.
Replacing a water heater: what a visit involves
The exact sequence varies with the house, but the major steps are the same.
Confirm the replacement
The plumber checks the tank, the venting and the water and gas or electric supply, then confirms the size and fuel type with you.
Drain and disconnect
Water, power and gas are shut off, the tank is drained and the old unit is disconnected from the pipes and vent.
Set the new heater
The new tank goes on a level base, often with a drain pan and a discharge line from the relief valve.
Connect and test
Supply lines, valves and gas or electric connections go on, then the tank is filled and tested for leaks and venting.
Check the safety devices
The relief valve, expansion allowance and flue draft are checked before the unit is left running.
You decide on the plan before work begins, and we explain what the permit step involves if your job needs one.
Sizing the new tank for your household
A tank that is too small runs out in the middle of a shower, and one that is too large wastes energy keeping extra water hot. The right size depends on how many people live in the house and when they use hot water.
| Household | Typical tank range | Notes |
|---|---|---|
| One to two people | 30 to 40 gallons | Smaller tank is fine if showers are staggered |
| Three to four people | 40 to 50 gallons | The most common size for a family home |
| Five or more people | 50 to 80 gallons | Large tubs or heavy laundry use may call for more |
| High hot water demand | Consider tankless or a larger recovery rate | Ask about gas input and electric element wattage |
Tell the dispatcher how many bathrooms you have and whether a soaking tub is in the house. We will suggest a size, and our tankless water heater page explains when an on-demand unit makes more sense.
Tank, tankless or heat pump
A conventional tank is the simplest replacement because it uses the same connections as the old unit. A tankless heater provides continuous hot water but needs correct venting, enough gas or electric capacity and regular descaling. A heat pump water heater uses less electricity but needs clearance, a condensate drain and a space that stays above freezing.
If you want to move from gas to a heat pump, tell the dispatcher so we can look at the electric panel and the room before quoting. We do not promise rebates or savings figures, because incentives change and depend on your utility and your house.
Permits and Maryland Heights rules
Ask the building division
The City of Maryland Heights residential plumbing permits page says a permit can be pulled without plans for replacing water heaters up to 120 gallons. That means a standard home replacement is a permit job that does not need drawn plans, though a permit is still a step in the process.
Call the Community Development building division at (314) 291-6550 and ask what applies to your job. We explain the permit step before work starts, so there are no surprises when the inspector is scheduled.
Sudden failure or planned replacement
A tank near the end of its life often shows signs. Rust in the hot water, water pooling at the base and a rumbling burner or element are all reasons to schedule water heater installation before the leak arrives.
A planned replacement gives you time to choose the model, the size and the day. An emergency replacement still goes smoothly when you can describe the existing tank, but you have fewer options in a hurry.
What affects the price of replacement
We give a clear price before work starts. These are the factors that change it.
Unit type and size
A 40 gallon electric tank and an 80 gallon high-efficiency gas unit are very different jobs.
Venting and gas work
A new flue liner, a longer gas line or a relocated vent adds time and materials.
Code upgrades
An expansion tank, a drain pan or a new discharge line may be needed to bring an older setup up to current practice.
Access and location
A tank in a tight attic or a finished closet takes longer than one on an open basement floor.
Timing
An after-hours emergency call is priced differently from a planned weekday visit.
Ask your insurer about water damage, and call our dispatch line for your real number.
When the old heater was repaired before
If you are replacing a heater that was recently repaired, our water heater repair page explains why a part swap sometimes only delays a failed tank. We also serve Bridgeton and the 63044 and 63146 ZIP codes with the same replacement service.
Permits, codes and the tank itself
The City of Maryland Heights says a permit can be pulled without plans for water heaters up to 120 gallons. Under the codes the new tank needs a working temperature and pressure relief valve piped to a safe drain, and gas units need a vent that meets the manufacturer's installation standard.
If you want the code text itself, the International Plumbing Code (IPC) is the usual model, though the city decides which edition it enforces. The building division can say which one governs a tank swap at your address.
Water heater replacement questions from Maryland Heights homeowners
Yes. When a tank has failed outright and is flooding the utility room, call whenever it happens. Dispatch is open 24/7, a same-day replacement is possible when stock and schedules allow, and the number is explained before anything is disconnected.
The city says a permit can be pulled without plans for water heaters up to 120 gallons. Call the building division at (314) 291-6550 to confirm what applies, and we walk you through the permit step when it does.
Most families use a 40 or 50 gallon tank, and larger households or soaking tubs may call for more. Tell the dispatcher your bathroom count and daily hot water use and we recommend a size.
Often yes, though tankless needs correct venting and enough gas or electric capacity. The plumber checks both before quoting, and our tankless page explains the descaling it needs in hard water.
Ask the plumber what the plan is before the visit. Leave the old unit in place until the plumber is there, because the drain valve and shutoffs need to be working.