Most water heater failures come down to one component, such as a thermocouple, gas valve, element, thermostat or dip tube, and replacing it is often far less work than a new heater. Water seeping from the tank body is the exception, because a rusted-through tank cannot be patched. Call the number on this page to be connected with a local plumber in Denver.

Common symptoms and what they point to
| Symptom | Likely cause |
|---|---|
| Gas unit, pilot keeps going out | Thermocouple, flame sensor or draft problem |
| Electric unit, no heat | Burned element, thermostat or tripped reset |
| Hot water runs out fast | One element down, broken dip tube or heavy sediment |
| Rumbling or popping | Sediment layer on the tank bottom |
| Puddle under the heater | Fitting, drain valve or relief valve, or a failed tank |
Safe checks before calling
Look at the breaker on an electric unit. On a gas unit, relight the pilot only by the steps on the label. If the relief valve is releasing water, leave it alone and never plug it, since it keeps the tank from over-pressurizing. Anything involving the gas valve, the flue or 240-volt wiring belongs to a professional.
Denver water and sediment
Denver Water calls its supply soft to moderately hard. It runs harder in the southern part of the system and during winter. That means mineral buildup varies by address and season, but flushing a few gallons from the drain valve once in a while still helps. Hot water that smells like sulfur usually involves the anode rod, which a plumber can swap.
Is the heater worth fixing?
The U.S. Department of Energy says a storage water heater lasts 10 to 15 years. A heater well inside that range with a dry tank is usually a repair. One near the end of it that needs a costly control may be better replaced. The serial number on the label encodes the manufacture date, and the plumber can decode it.
What drives the bill
- The part and whether it is in stock
- Gas or electric
- Access, since closets and tight utility rooms add labor
- Whether the visit is during regular hours
Ask for the diagnosis and a quoted price before the work starts.
Helping the plumber on the phone
Before the visit, note whether the heater is gas or electric, its tank size in gallons from the label, roughly how old it is, and exactly what changed: no hot water at all, short supply, odd noises or a leak. Mention whether the unit sits in a basement, a garage or a closet upstairs. Those details let the plumber bring the likely parts and give a better sense of the job before arriving, which can save a second trip.
Water Heater Repair questions from Denver homeowners
Why does my gas water heater pilot keep going out?
Is Denver water hard on water heaters?
How long should a tank water heater last?
Can a leaking water heater be repaired?
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Helpful guides
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Sources
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