On Apr 23, 10:58*am, "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

Much more common in Europe as we understand it. They use a lot of heat
for the very short period of time that hot water is needed and that is
claimed to be 'overall' (over long period of time) more efficient than
heating and having a tank of water kept hot all day and night.

Most "Instant Hot Water Heaters" we understand are 'electric tankless'
heaters. And use many kilowatts for the very short periods of time
they are in use. Some claim them to be totally adequate; others find
that if, for example someone is showering, there is not adequate hot
water to rinse a few dishes, so they install a second one for say the
kitchen or a second bathroom.

Have seen (tankless) numbers ranging from nine kilowatts to fifteen
kilowatts. That needs fairly heavy wiring, but again they only draw
electrcity when in use.

Based on our experience with 40 US gallon electric hot water tank
heaters, am not personally convinced that they are that much less
efficient than 'tankless' heaters.

Typically our tank heaters have 3 kilowatt heaters and in any case any
heat that even well insulated ones do lose help warm the house!

Perhaps a reasonable alternative for the OP could be a typical 3
kilowatt electric 40 gallon tank? Very easy to install needs
reasonable wiring and will typically last 10 to 15 years. Perhaps in
same space and using same plumbing as the gas heater but does not need
a flue/chimney or gas lines.

Here the basic cost of such a tank is less than $300** (not installed)
and our electricity cost is about ten cents per kilowatt/hour. Our
electric utility mentions that about 8% of a typical, all electric
family home, cost is for hot water. So in our case that means that our
hot water costs a bit less than $20 per month. (All charges incl,
sales tax.)

This is cool climate; most months need some home heating, especially
during cool evenings. So again some of the heat from hot water that
doesn't go straight down the drain helps slightly to warm the house.

So just a suggestion.

Our most current tanks ** are US made and sold here in eastern Canada.
(Haven't yet seen a Chinese one!!!!!).

There is by the way planning for a large additional hydro power
project 'The Lower Churchill' in Labrador, that will supply power to
the north east USA and eastern Canada during next few years. This will
be a reasonable and less polluting alternative to coal, oil or even
atomic generation. And since it will be using 'renewable water power'
will also keep electricity rates at a reasonable level;.