"Al Bundy" wrote in message
...
" wrote in
ups.com:


Phil Scott wrote:
wrote in message
oups.com...
Greetings,

I am replacing an existing boiler in a 700 sq ft house.
What is the
CHEAPEST natural gas boiler I can buy of at least 60,000
BTU
online or
otherwise. This seems like a question I should be able
to
answer with
google.com but I had back luck so I am asking the
experts.
You guys.

Thank you for your time,
William


A lot of people use water heaters for that purpose.
those
are cheap. you will have to check the btu/hr heat input
rating and select accordingly, for 60,000 btu/hr you
probably
need a 30 gal high recovery rate water heater... cost
probably
under 400 dollars.. could be a little more.

Then just hook it up to your hot water circulating
pump...dont
forget to fit an expansion tank.. the bladder diaphram
type
will be best for your application, a small one, about 5
gal
total capacity... no valves between the expansion tank and
the
hot water outlet of the heater. you can locate the
bladder
type anwhere you want...be sure to read the directions.


That should last you about 10 years, maybe 20 years in
house
heating service conditions.... its a closed loop, so there
will not be any scale build up issues.



You might consider a 40,000 btu model for a house that
small,
then suppliment with a 50 dollar electric heater in your
bedroom for cold nights on occasion. that would be
about
200 dollars cheaper.


Is it legal? check your local city building inspectors
dept.
they may require you to fit an approved **low water
safety
shut off*** , but maybe not... the smaller you go the less
is
required for ignition and low water protection...an
advantage
if you go to the 20 gallon heater. Be sure to fit the
standard hot water heater pressure relief valve regardless
..thats critical.


The city may want a back flow preventer on the cold water
make
up line. you may or may want to ask, since its somewhat
of a
self sterilizing loop if you set the thermostat over
200F...
and you will not be treating it with chemicals that is not
entirely critical issue (as it is with larger boilers
that
chemically treated water in loop that you want to keep out
of
the city mains in event of loss of city water pressure
etc).
There are bacteria that live in hot water though and you
wouldnt want that back flushing into your city water line,
so
minimally I would install a swing check valve... and
discuss
it with the city.

If someone sets the thermostat below 120F you can get
dangerous bacteria growing in the heater and water
distribution lines...and that could happen later, after
you
are gone etc.



Buy it for the correct fuel, natural gas or propane. they
have different jet sizes.






Phil Scott



Greetings,

The boiler rating is 60K for such a small house because the
house is a
row home built in the 1800's and is not (well) insulated.

Im sure thats about right...however the max design condition
is only approached 2% of its run time... that means that 98%
of the time a correctly sized boiler is over sized... and 2%
of the time its right sized, and maybe 1% of the time its a
little undersized.

by going to 40,000 btu it will be undersized maybe 4% of the
time... thats livable if you have an electric heater in the
bedroom for those days. If low cost is a concern thats an
issue..also with the city code requirements for low water
protection etc.


when talking to the city on this issue be sure you dont become
aflicted with an idiot... be prepaired to question any replys
and ask for a reference to the Uniform Mechanical Code if they
decline the use of a hot water heater for your purpose.


Phil Scott




The houses
on either side have been torn down so there is a lot of
surface area to
volume.

I wish I could use a water heater to heat the home but I am
almost
certain the town will not allow it because I have never
seen such a
setup. However, it doesn't hurt to ask and I will on
monday if I don't
have a new boiler in by then.

Thanks for your very informative reply,
William



The houses
on either side have been torn down so there is a lot of
surface area to
volume.

Park a couple of doublewides on each side and rent em out.
Income +
insulation.