If you smell gas, leave the building now and call the gas utility and emergency services from outside.
If a carbon monoxide alarm sounds, leave the home and call emergency services from outside.
How a gas water heater works
A burner under the tank heats the water, controlled by a gas valve and thermostat on the front. On older models a standing pilot stays lit; newer ones light electronically. Combustion gases rise through a flue running up the centre of the tank and out through a vent pipe, either into a chimney or, on power-vented models, through a side wall with a fan. Safety devices shut the burner off if the flame is not detected or if the venting is not working as it should.
Because all of that is gas, flame and venting, almost nothing on a gas water heater is a homeowner job. The good news is that most faults are in replaceable parts.
Gas water heaters in Connecticut homes
You will find them across Connecticut's cities and larger towns wherever gas service runs: in older multi-family buildings, city colonials, postwar suburbs and newer subdivisions. In older urban houses they often sit in tight basements with low ceilings, narrow stairs and venting arrangements that have been changed over the decades. That makes access and venting two of the main things a technician considers on any replacement. See multi-family water heaters for buildings with several.
Common problems
- No hot water: a pilot or igniter problem, a failed flame sensor or thermocouple, a faulty gas control, or a venting safety shutoff
- Burner lights then goes out: often flame sensing, sometimes a draft or venting issue
- Not enough hot water: sediment, a broken dip tube, a control issue or a heater too small for the household
- Water around the base: condensation on a cold start, a leaking fitting or drain valve, or a failed tank
- Power-vent fan faults on side-wall vented models
Most gas heater faults are a single part.
What to leave alone
- Relighting the pilot or adjusting the gas control
- The gas line, shutoff and connector to the heater
- The flue pipe, draft hood and any side-wall vent
- The relief valve and drain valve
- Any wiring on power-vent models
We do not give pilot or relighting instructions. A burner that has shut down may have done so to protect the house, and it needs a technician's eyes.
How repairs are done
The technician checks the gas supply to the heater, the ignition system, flame sensing and the gas control, then the venting and its safety devices. They look at the tank for leaks and at the bottom for sediment. Once the fault is found, they explain it and give you the price before replacing any part. After the repair, they run the heater through a heating cycle and check the venting is working.
Replacement and venting
A tank that leaks from its shell needs replacing. Like-for-like replacement of a gas heater is usually straightforward, but venting deserves attention: a new heater has to be vented to suit that specific model, and changes in the house over the years, such as a boiler replaced by a unit that no longer uses the chimney, can affect how a water heater vents. The installer assesses this on every replacement. See venting and chimney assessment.
Replacement is also a moment to consider a tankless unit or a heat pump water heater, if the space and household suit either.
Atmospheric, power-vent and condensing units
Gas water heaters come in a few broad types, and the type shapes both repair and replacement. Atmospheric heaters rely on warm exhaust rising through a flue into a chimney; they are the simplest and the most common in older homes. Power-vent heaters add a fan that pushes exhaust out, usually through a side wall, which frees them from needing a chimney but adds an electrical connection and a fan that can fail. Condensing units extract more heat from the exhaust, produce condensate that must drain, and vent through dedicated piping. When a heater is replaced, moving between types changes the venting and the space needed, which is why the installer asks about the current setup first.
Gas heaters in older city basements
In the older housing of Connecticut's cities, gas water heaters often sit in tight basements shared with meters, a boiler or furnace, and years of stored belongings. Stairs are frequently steep, ceilings low, and some basements are reached only from outside. Replacement heaters have to come in and old ones go out along that route, and venting often joins a chimney that other appliances also use. Describe the basement when you call; it helps the installer bring the right help and plan the venting.
What to expect after a new gas heater goes in
A new tank will often drip a little condensation for the first heating cycles as the burner warms cold water; that settles. You may notice the burner running longer than you remember at first, simply because the whole tank is heating from cold. The installer should show you the gas shutoff for the heater, the water shutoff, where the rating plate is, and which settings are yours to adjust. Keep the area around the base and the draft hood clear of stored items.
What affects the cost of gas water heater service
- Which part has failed and whether it is carried on the van
- Atmospheric or power-vented model
- Venting changes needed on replacement
- Access in tight city basements
- Emergency hours versus a scheduled visit
Every repair is priced before it begins.
How long gas water heater service takes in Connecticut
Many gas water heater repairs are done in one visit. Like-for-like replacements are usually a single visit too. Venting changes, relocations or difficult access can take longer. After any repair or replacement, allow time for the tank to heat from cold.
Gas water heater questions
My gas water heater pilot keeps going out. Why?
Common causes include a failing thermocouple or flame sensor, a draft or venting problem, or a faulty gas control. Because some of those involve venting and safety devices, it needs a technician rather than repeated relighting.
The pilot has gone out. Is that something I can deal with myself?
We do not give relighting instructions. A pilot that has gone out may have been shut off by a safety device for a reason. Call a technician, and if you smell gas, leave and call the gas utility and emergency services from outside.
Why is there water under my new gas heater in the morning?
Often condensation. When a gas burner heats a tank full of cold water, moisture condenses and can drip. It usually stops once the tank is up to temperature. If it continues, have it checked for a leak.
Does a new gas water heater need a new vent?
Not always. The venting has to suit the new model, and the installer checks the existing arrangement. Sometimes it can be reused as is; sometimes changes are needed. They will explain before starting.
What is a power-vent water heater?
A gas water heater with a fan that pushes combustion gases out, often through a side wall rather than a chimney. It needs electrical power to run. The installer will say whether one suits your house.
Do you work on gas lines?
The local installers make the connection to the water heater as part of repair and replacement. Wider gas piping and the gas supply to the house are outside this service.
Can a gas water heater go in a tight basement?
Usually. City basements are often cramped, and the installer plans the route in and the venting around the space. Describe the stairs and headroom when you call.
Should I switch from gas to something else?
There is no single answer. Gas heaters are simple and quick to recover. Heat pump and tankless units suit some homes. The installer can talk through options without pushing any one choice.