oil boiler conversion to gas
Looking for a little advice on this one. I need to break this question into a couple parts. I hope it doesn't make this confusing but we want to convert our current house to gas heat and our old house that we converted to a rental we'd like to do the same hence the two different scenarios.
First off, our current house is about 600' away from the end of the gas main. I'm working with the neighbors and the gas company to see how low I can get the price down for extending the line but that's a different story (although it factors into my ROI).(return on investment)
Current system is hydronic baseboard with 185000 WM boiler and indirect HW heater on 2400 sf split level brick house. We typically use about 850 gallons per year and supplement with about 1.5 cords of wood in a stove on the main floor. I'm in the process of adding insulation to the attic (current 22 will add 30 plus cover/seal top plates)(no insulation in the walls). Also hope to do rigid foam wrap on basement walls over the winter but worse case this will happen next year. I've also sealed as many things as I can in the house (around light fixtures, can lights, wires running through walls and outlet covers.) Windows are mostly double pane with a few exceptions and doors aren't too bad but will all eventually be replaced.
The guy initially just took down all the information and said he'd get me a quote going in the next couple of days. I asked him how to determine the proper boiler size and he said we can measure the length of the baseboard to get an estimate (worries me he didn't do this prior to my question). Is this even enough to determine proper size?
He offered several options: 84-85% efficient boiler with indirect hot water tank
84-85% boiler with separate water tank
90+% boiler with separate water tank (wasn't promoting saying it would take 15+ years to get ROI.) I do need a new chimney liner which wouldn't be needed with this option.
He wasn't big on offering on demand water saying people were complaining about the hot cold change in the supply because of hot water in the lines from the previous demand having a gap of cold before it heats up again. (I don't see the issue. It sounds like something you just get used to.)
He mentioned if we go with a separate hot water tank we can bring down the BTU's even more for the boiler.
1500 sf house single level with hydronic baseboard 105000BTU with inner coil hot water. All new Anderson windows, insulated walls (15),ceiling(38). They use about 600 gallons per year.
Pretty much the same options he offered. He said they don't do gas powered boilers with the inner coils any more so that's not an option.
Overall I'm not too impressed with this guy. Waiting for the next contractor for next week (If Sandy doesn't delay that...)
Any thoughts or advice at this point?