Jeff Wisnia wrote:

A friend who's facing replacement of a 60 gallon gas water heater asked
me what I knew about electric tankless heaters.

The "family" is two adults living in a single family house in the Boston
Area.

I've no firsthand experience with tankless heaters. The bit of stuff
I've read leads me to believe that installing a whole house tankless
unit as a replacement for their gas fired heater is very likely going to
require increasing the capacity of the electric service to their house,
along with the installation a new panel and heavier conductors from the
panel to the tankless heater location.

The incoming water supply temperature around here gets into the low 40s
during the winter, requiring a pretty powerful tankless heater in order
to raise that to a comfortable temperature for showering, even with a
low flow showerhead.

And, if one person is showering and the other starts the clothes washer
and then decides to do the dishes, things could get coolish in the
shower, huh?

I'm thinking they'll be needing at least a 125 amp 220v circuit for the
heater, which will almost certainly necessitate the electrical changes
mentioned above.

Comments from those in the know?

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.

Why would they not replace a gas tank type with a gas tankless type?
Either way, the tankless type have lower standby losses than the tank
type which may or may not matter much depending on the usage patterns
and unit location where the lost standby heat goes.

I don't know what the various utility rates are in Boston, but I though
I heard NU had like a 20% rate increase recently. Surely gas is cheaper
especially if they already have gas service in place vs. needing to
upgrade electric service.

Pete C.