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Steve Barker[_5_]

wrote:
On Apr 23, 9:54 am, ransley wrote:
On Apr 22, 11:40 pm, Steve Barker wrote:

Jimi wrote:
Hello,
I just had a person that rates houses for energy efficiency come and
rate our house. One of his suggestions he made was to pull out my existing
Gas fired hot water tank and install a Tankless hot water heating system.
We don't have a family living here only my wife and I and we're both away
through the day working .....so the hot water demand is only morning and
evenings. It makes sense when he explains it. He says "why have a large tank
down there heating water 24/7 when your demand is about an hour a day?"
Are there any disadvantages to this tankless system? Does anybody here
have one that would care to comment? Thanks.. Jim
Disadvantage? yes, you'll never get 140 degree water out of it for your
dishwasher. and they cost a fortune.
There are tankless designed to do 180 all day long, but what a waste
it is to heat a tank to 140 just for dishes. My dishwasher has a
preheater and I would never buy one without. An AO Vertex or Cyclone
is also expensive, saving energy is an investment and it costs money.

Yes, I don't see why you can't get 140F water out of a tankless.
They are spec'd for a given temp rise. All you need to do is figure
out your incoming lowest water temp and what flow rate you want to
support to size the unit. I have my tank set at about 130 and the
dishwasher works fine.

Yes, they have a certain temp rise capability. And it ain't a hundred
degrees. The incoming water in our area in the winter is about 38
degrees. Heat that with a tankless and it'll dribble like an old man
with an enlarged prostate.

s