The higher the energy factor the more efficient the water heater.
Tankless water heater requirements.
Today tankless water heater energy factors range between 64 and 91 for gas fired models and up to 99 for electric models.
How to determine the required size of a tankless hot water heater.
Vent termination all tankless water heater vents must terminate at least 4 feet from a property line.
Below we ve highlighted what size water heater you would need in our example of 6 5 gpm at a 63 f temperature rise.
The remaining heat creates a hot exhaust gas that requires metal venting typically stainless steel or thick aluminum.
For homes that use 41 gallons or less of hot water daily demand water heaters can be 24 34 more energy efficient than conventional storage tank water heaters.
As a general rule any gas heater which is tankless uses combustion air must have a minimum area of 10 000 cu.
Ok so san jose has the following requirements for where to install the tankless water heater.
Determine your water flow rates.
Tankless water heaters are much smaller than units with a storage tank allowing them to be wall mounted.
You re only looking at 20 to 100 out of pocket as opposed to several hundred dollars to call in a plumber.
With a condensing tankless water heater you don t need metal venting.
This is as easy as heading down to the local planning or building department to ask for one.
Once you have your total flow rate and the required temperature rise you can find the right size tankless water heater for your home.
Determine the mounting space.
Measure your cold water temperature.
Enclosed areas just as closets might need air ducts and extra air inlets.
The models which need combustion air from the outside are required to have a second hose which is supposed to be put in.
Tankless water heaters can be 8 14 more energy efficient for homes that use a lot of hot water around 86 gallons per day.
For a household of one or two people a tankless electric unit will probably be adequate.
Simply locate the appropriate water heater sizes on ecomfort using your information.
Around the water heater.
The first permit is for the water heater itself.