: Thanks

Todd,
I installed a unit from Rinnai last year for my
whole house and I love it.
You will save enough in a few years
to pay for the unit, and it should last 4x as
long as a tank heater (10 yr warranty). The flow on mine is
6.3 Gal/min at up to 180,000 BTU (about 54 F temp rise).
Enough for 2 showers and then
some. The only time I have noticed a reduced flow
at a lav is when I open the 3/4 valve on my large
tub, but then, I only have a 3/4 service.
(I think it is insane when plumbers install a
separate tank heater just for a spa.)
This unit is specd as a boiler and is used in
comercial applications replacing large tank
heaters for hotels with a much smaller tank.
The only consideration is that it should be mounted
outside for venting and 3 feet away from openings.
It is freeze protected to -30 C.
Other models an vent to flue or power vent.
Avoid unregulated (fixed heat) units. Most
are wimpy and only good for limited use such
as one shower or for cabins/boats.