On Apr 9, 1:19*pm, Paul M. Eldridge
wrote:
"ransley" wrote

1 - At least one regular poster here continually mentions the
winter benefit of heat loss without regard to where the water
heater is located and totally ignores the AC impact in the summer.

Hi Mark,

The impact of standby loss with respect to added a/c demand is
generally very modest for three reasons:

*1) with the exception of some of the southern most states, heating
degree days exceed those of cooling throughout most of North America,
in some cases by a factor of ten or more (e.g., Minneapolis MN).
Pittsburgh PA, a mid-eastern seaboard city, has 5,968 HDD and 654 CDD.
Even in San Diego CA, heating demands exceed those of cooling, i.e.,
1,256 HDD versus 984 CDD;

*2) *generally speaking, water heaters are located inside conditioned
spaces in colder regions due to the risk of freeze damage whereas they
are typically placed in non-conditioned spaces (e.g., attached
garages) in warmer climates -- located outside the home's thermal
envelope, there would be no impact on cooling demand;

*3) for every kWh used, an air conditioner will remove three or more
kWh of heat. *A 10 SEER air conditioner will purge 2.93 kWh of heat
for every one kWh consumed and a 13 SEER air conditioner (the current
minimum standard) will eliminate 3.8 kWh of heat. *Thus, each kWh of
standby tank loss translates to 0.34 kWh of cooling demand at 10 SEER
and 0.26 kWh at 13 SEER.

Taken together, it's pretty clear the benefits in terms of heat gain
far outweigh any potential loss with respect to added cooling demand.

Cheers,
Paul

Hi paul, I really dont see much of either heat gain winter or summer,
Im just arguing against misinformed oposition. I see a flue going up
the uninsulated part of the tank going outdoors. I guess im a little
****ed at negatives thrown at tankless by people that never owned one,
and post wrong information. I own one, I can see on my 9$ summer gas
bill, I see a short payback, and I cook all food on a gas stove and
have a gas dryer. Tank Energy Factor is what nobody wants to
aknowlegde. Energy Factor for Tanks are about 52-60, and it simply
means, in fact, if your tank is a 60 E.F., $0.40 of every dollar you
pay to heat water is wasted. Tankless EF ratings are near Total
efficencies, Tankless EF ratings are from 82-95 [95 for a condensing
Takagi] We have all these folks here who put down tankless with bogus,
stupid, bad, information. Granted tankless are not for all, but they
are designed to last 30 years since the coil is thick copper pipe,
they save money, they have drawbacks you must learn to live with, but
I like saving money and not paying utilitie companies. I did so well
with a 110 yr old house, lowering utilities from maybe 1500 a year to
550 that the gas company came out to see how was I stealing gas. I was
told by Nipsco my house is the most efficent they have seen. I heat
1800sq for no more than $105 at max -14f lows. Tankless can cost alot
more, but can cost the same, last longer, and save enough to pay you
back, very quickly. Quickly, and that is at todays Ng gas prices, with
oil over 100 a barrel, it`s going to rise real dam fast. Your payback
will be sooner with every Ng price increase, and last I read, new NG
field are not being opened from NIMBY bs, consumption is outpacing
production, that`s why LNG dockyards are being built, so we can IMPORT
gas on tankers, even though we have it in the ground. We have no
energy policy, we have no education. Even England mandates only
Condensing heating units, and England is an Exporter of energy. We are
an Importer. Dam I should run for President and give America an
Energy agenda.