The thought of adding a complete
central heating system to an
existing house conjures up
images of hours of "Sawzall surgery" followed
by more hours of repairing drywall
and finishes. This is especially true
for forced-air systems, with all their
associated ductwork.
But with the right approach, central
hydronic heating can now be added to
many homes with minimal disruption
to existing finishes.
Advantages of Water
When it comes to retrofit systems,
hydronic heating has a basic advantage
over forced air. The water used to convey
heat is almost 3,500 times more "thermally
concentrated" than air. A cubic
foot of water absorbs about 62.4 Btu for
each degree Fahrenheit its temperature
increases. By comparison, a cubic foot
of air only absorbs