DIYbanter - View Single Post - 40 gal just not enough: Replacing water heater for 2400 sq home. Family of 2 adults + 2 children

Wayne Whitney

On 2008-04-09, wrote:

the last link you posted in my response to your claim 20% went up
chimney said 13 % up chimney.

First, I am the source of the 13% up the chimney number. That is just
a rough estimate based on the total 20% standby losses of a gas tank
(gas tankless EF 0.80 - gas tank EF 0.60) compared to the 7% standby
losses of an efficient electric heater (0.98 EF of an electric
tankless - 0.91 EF of an electric tank). The difference is
attributable to the flue on a conventional gas tank.

But the 20% standby losses is the more important figure. The losses
through the tank periphery are still losses--they can only be
considered otherwise if the tank is in conditioned space and you are
in a heating-only climate.

DOES YOUR TANKLESS HAVE A PILOT LIGHT???????

No, there's maybe only one model on the market today with a pilot
light, out of tens of models.

Wayne