We're getting a new oil boiler to replace what looks like a 40 yr old oil boiler. Just bought our first house, which was built in 1970. It's a 2000 sq ft colonial, 2 floors, 1/2 finished basement, 4BR, 1.5 bath. Original 19 single pane windows with storm windows, no sliding doors. Two entry doors both with new storm doors. Attic could use a bit more insulation, but it's not awful. I'd say the home has average insulation. I have not done a heat loss calculation, but if I rough out about 50 BTU per sq. foot, that's around 100,000 BTU. We'd want the option of adding an indirect water heater at a later date, but not yet. It's a chimney vent. House is in New England in the 6500 heating degree days zone.
I have about 5 quotes for boilers. None of them did a HLC and only a couple of them actually walked around the house to check the hot water baseboards and the rest.
The quotes I got include Buderus models G115/28 (98,000 BTU), G115/34 (120,000 BTU) and a G215/3 (134,000 BTU).
The G215/3 guy was recommended by neighbors & has the lowest quote, but I wonder about his boiler choice. He said he wasn't going to do a Heat Loss Calculation and he chose that boiler based on his 30 years experience and what was already there. (But who knows if the original boiler was sized correctly.) I pressed him about his choice concerned about it being oversized and he talked about how he can ratchet it down to 80% of the output anyway we'd need that size for future indirect water heater. I asked why his nobody else had quoted a G215 model and he said it was because the G115 models come put together already so they don't have to do assembly like he does with the G215. I sort of feel like I was getting the "don't you worry about that pretty little lady" treatment, but hey - what do I know? Any merit to his arguments?