Gas on-demand units
Several showers running every morning? A gas tankless unit handles it, as long as the gas pipe and vent are sized to match.
Sizing
A tankless gas hot water heater is sized by flow rate in gallons per minute and the temperature rise it has to deliver. Two or three bathrooms usually call for roughly 8 to 10 GPM, measured at January inlet temperatures.
An undersized unit cuts out or runs lukewarm when two showers run together, so the installer counts fixtures before naming a model.
Venting
Whole-house gas units in Houston homes can draw around 150,000 to 199,000 BTU at full fire, far more than a tank. That often means a larger gas pipe from the meter, and sometimes a meter upgrade from CenterPoint Energy.
Fuel
Standard wherever gas service reaches the street. The meter and pipe size cap how big the unit can be.
For homes without natural gas. Needs a propane-rated unit, a correctly set regulator and enough tank capacity.
Avoid indoor vent runs and suit many exterior walls.
Have gas service? Get the line sized before you buy.
Call (832) 783-9416Price
Expect a typical installed range of about $1,500 to $2,800 depending on flow rate. Converting from a tank adds fuel pipe, vent and drain work.
Tankless gas water heater installs are a common upgrade for families who keep running out. See instant water heater basics on the home page.
Freezes
Outdoor gas units in Houston, TX have built-in freeze protection, but it runs on electricity. During the February 2021 winter storm, many homes lost power, and exposed water lines froze.
Insulating the water lines, keeping the unit plugged in, and knowing how to drain it if the power goes out are cheap insurance. An installer can show you the drain valves when the unit goes in.
Before you buy
A larger unit may need a bigger gas meter from the utility.
Where the vent can exit decides indoor versus outdoor models.
Built-in pumps bring hot water to far taps faster.
Fuel and venting
Yes. They need an outlet for the controls and fan, so they stop during a power outage.
Usually not. Tankless units need PVC or stainless venting rated for them.
Yes. Outdoor models avoid indoor venting but need freeze protection.
Gas, for whole-house use with several fixtures running together.
You're put through to a local installer who checks the gas line and quotes the job.
Describe your home, fuel and existing unit, and we'll put you through to a local installer in Houston, Texas.
