Im a 2 month lurker making my 1st official technical post on the forum but have learned a great deal from the info here. Am planning a new boiler installation here in the next month or so. Have a ranch house with ~1800 sf heated space, 111 feet of 1/2" cu tube/Al fin baseboard, heat loss of the house is estimated at 55,000 BTU/hr. My current boiler is a wood/coal burning unit that was retrofitted for oil rated @ 143000, the tankless coil is plugged up and not used, and am using a 50 gal electric HW heater. There are 3 heating zones, 1/2" cu tube for supply & return piping, but the valves & manifold are 3/4" along with the boiler water return piping main, and 1 taco circ pump on the return side of the boiler. Have an intact clay lined chimney that is in the middle of the house. 4 people occupy the house.
Done lots of research and still am on equipment. As much as I like the Buderus G115, I don't like it's pricetag and am right now settling on the Biasi B10 w/ Riello although the Burnham MPO IQ was suggested to me as well.
So, here goes my questions:
1. is the Biasi B10-3 sufficient for the house & 40 gal indirect HW heater?
2. Is an indirect water heater really going to save money? Right now I pay $3.64/gal #2 fuel and $0.099 kw-hr. The fuel heating value & cost factor to $0.088 kw-hr. But it boils down to efficiency, right? Or is it something entirely different?
3. Going to try the new boiler without an outdoor temp reset for the 1st year, then maybe add it on. Does this feature really make a difference?
4. Circ Pumps - Grundfos Alpha or TACO circ, which do you guys prefer?
5. Indirect water heaters - coil heating bundle vs tank-in-tank design? again, which do you guys prefer?
Thanks in advance for the input. Gd night~