On Sun, 25 Nov 2012 04:28:18 -0800 (PST), "
wrote:

On Nov 24, 4:56Â*pm, Vic Smith wrote:

This is the best part of the posted article.

"Theres still another concern €” and another possible cost €” if a home
has a standard 40- or 50-gallon gas water heater. Those heaters are
generally vented through the chimney along with the older furnaces.
But after removing the old furnace venting pipe, there is not enough
heat generated in the chimney by the water heater venting pipe alone
to prevent condensation from occurring. And that condensation will
include sulfuric acid, which can eat away at a chimneys mortar
joints. Re-venting the water heater could increase the total cost of
the new furnace project by $3,000 to $4,000, Baum said."

So in that world gas furnaces run winter and summer to provide draft
for the water heater. Â*Strange world.
But does add "$3,000 to $4,000" to get the Chicken Littles flapping
and clucking.

Not a strange world. The issue is that an orphaned
water heater typically winds up on a chimney that is
now way too small, because it was sized for both the
water heater and a gas furnace. Drafting is NOT the
issue. Condensation is. In the winter in a chimney that
is not entirely contained within the heated part of the
house, condensation occurs because the gases now
cool off too much. With a furnace also running, the
chimney was kept warm enough so that this would
not happen. And that condensation, over time, will
destroy the mortar in a chimney.



Yabbut...winter or summer a water heater will run into a cold chimney.
And so will the furnace. Chimneys cool off fast in winter.
That's why there are few unlined chimneys left.
Talking about NG only. Haven't had coal or oil in decades.
Condensation talk is to sell liners to those who don't have them,
or to now sell a hi-efficiency water heater with a dedicated vent.
You still see the salesmen and cracker-barrel "experts" using the
"orphaned" water heater draft argument, but when people realize the WH
was always an orphan, they turn to the acid argument.
Anyway, "$3,000 to $4,000" is a BS number.
A typical SS liner is WAY less than "$3,000 to $4,000."
And so is a typical high-efficiency HW tank with a dedicated vent.
DISCLAIMER: Chimney condition is important for your safety, and the
above isn't meant to suggest otherwise. If you don't know your
chimney is in good condition, have it examined by a professional.