ls02 wrote:


1. Can hydraulic radian heat under wood floors be the primary or the
only source of heating? My architect said No, it can only be used or
comfort, and need to be supplemented by other heat source.

Perhaps you need a new architect. Yes, it can be done, I've seen it done.



2. Is there way to combine boiler used for radiant heating and for hot
water? My boiler is small and old and needs replacement anyway. If i
decide installing radiant heat in part of my house it would be the
best to use the same boiler.

Yes, but the water may need to be at different temperatures for different
uses. Water heaters can be indirectr fired through a heat exchanger and it
is very efficient that way.



3. Can wood floors survive heat underneath? I know wood is extremely
sensitive to temprerature.

Yes, it is not all that hot.



4. How expensive hydraulic radian heat vs. standard forced air gas
furnace? I have electric radiant heat in my two bathrooms and kitchen
under tiled floor and it is very expensive to run.

Electric heat is often two or three times the cost of oil or gas. I don't
know the comparison between the radiant and hot air though, but a good
heating contractor may.



5. Can the same boiler be used to heat baseboard radiators? My
architect said it is the cheapest way to heat th house.

Yes, but again you may need different temperatures on different zones if you
are mixing heat types. Baseboard runs with water in the 170 to 180 range
while radiant is about 120, IIRC.


6. Can hydraulic radian heat installation be DIY? Assuming there is
professional layout and calculations done, it seems to me at least
part of installation can be DIY.

Yes, there are many different types used depending on construction. Some is
done from above, others below.

In any case, if the boiler is old you can save a lot of money with a new
one. I had a System 2000 by Energy Kinetics installed last year. My oil
bill for the last 49 weeks dropped 39.4% as compared to the 30 year old
boiler. Rebates may be available also, as well as tax credits.