Why do I have no hot water?
Taps run cold at every fixture, or hot water disappears after a minute or two. The heater may be silent, or it may run without ever heating the tank.
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Key takeaways
- This is usually not an emergency, but it does not fix itself and it gets worse if you leave it.
- Most likely cause: Pilot light or burner is out on a gas heater.
- Do this first: Check the breaker panel for a tripped water heater breaker and reset it once.
- Call right away if you smell gas anywhere near the heater. Leave the house and call the gas utility first.
- The repair starts with: Confirm fuel or power is reaching the heater.
What it is
No hot water No hot water means the water heater is not raising tank temperature, usually from a dead pilot or burner on a gas unit, a failed heating element or thermostat on an electric unit, or a lost power or fuel supply to the tank.
It is not an emergency by itself, but if you also see standing water near the tank, close the cold water shutoff on top of the heater and call a plumber right away.
The short answer
No hot water almost always comes down to one of three things. On a gas water heater the pilot or burner has gone out. On an electric water heater a heating element or the upper thermostat has failed. On any heater, a tripped breaker, closed gas valve, or a tank that is simply too small for the demand will do the same thing. If the tank is also leaking, shut off the water supply to it and call a plumber right away.
What it usually means
These are the causes we find most often, ranked from most likely to least.
- 1
Pilot light or burner is out on a gas heater
Most likely
A draft, a dirty thermocouple, or a gas interruption drops the pilot. The tank goes cold within hours.
- 2
Failed heating element or thermostat on an electric heater
Common
A burned out lower element gives short hot water. A failed upper element gives none at all.
- 3
Tripped breaker or closed gas shutoff
Common
Power or fuel to the heater was cut, often after other work in the house.
- 4
Sediment buildup insulating the burner from the water
Less common
Denver area hard water leaves mineral scale on the tank floor, which slows or blocks heating.
- 5
Water heater has reached the end of its life
Occasional
A tank past ten to twelve years often loses heating capacity before it starts to leak.
What to do right now
- 1Check the breaker panel for a tripped water heater breaker and reset it once.
- 2On a gas heater, confirm the gas shutoff at the tank is open and look for a lit pilot.
- 3Check whether the problem is every fixture or only one. One fixture points to a mixing valve, not the heater.
- 4Look under and around the tank for water. Any standing water changes this from a repair to an urgent call.
When it is an emergency
- You smell gas anywhere near the heater. Leave the house and call the gas utility first.
- Water is pooling under the tank or running from the relief valve.
- The tank is making loud banging or rumbling and the flue is hot to the touch.
What the fix involves
The repair depends on what failed. A pilot or thermocouple problem is a short visit. A failed element or thermostat is a parts replacement. A tank full of sediment gets flushed, and a tank at the end of its life gets replaced rather than repaired, because a second failure usually follows within a season.
- 1Confirm fuel or power is reaching the heater.
- 2Test the thermostat, elements, or thermocouple depending on the fuel type.
- 3Flush sediment if the tank is scaled but otherwise sound.
- 4Replace the failed component, or quote a replacement if the tank is past its service life.
What drives the cost
Every job is quoted before work begins. These are the factors that move the number on this kind of repair.
- Gas versus electric, and tank versus tankless
- Whether the fix is a single component or a full replacement
- Tank size and how accessible the heater is
- Whether code upgrades such as expansion tanks or venting are required
- After hours or same day response
Related problems homeowners ask about
Why won't my water heater pilot light stay lit?
The pilot lights while you hold the button, then goes out as soon as you release it, or it stays lit for hours and then drops.
Read this nextWhy is my water heater leaking from the bottom?
Standing water under the tank, a damp ring on the floor, or rust streaks running down the outside of the jacket.
Read this nextWhy is my water heater making a popping noise?
Popping, rumbling, or kettle-like sounds from the tank during a heating cycle, often loudest after heavy hot water use.
Read this next
Read more on this
This page is for triage and dispatch. These guides go deeper on how the work is done and what shapes the price.
Licenses, credentials, and company proof
- Colorado Master PlumberLicense MP-18927
- Colorado State Plumbing ContractorLicense 2110
- Family Owned & OperatedServing Denver since 2006, 20 years
- Better Business BureauAccredited Business, A+ rating
- Angie's List Super Service Award2012 through 2017
- Serving Denver since 2006Residential and commercial properties across the metro
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Before you book: pricing, timing, and guarantees
Straight answers on what no hot water work costs, how fast we can get out, and what stands behind the repair.
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Stop guessing and get it diagnosed
Family owned, licensed Colorado master plumbers serving the Denver metro since 2006.