I live in the mountains of western Maryland and have a 1903 Al covered 3 story house ~4500 sq ft plus full basement and attic but the boiler is only for the first 2 floors. The boiler is a National - U.S. Radiator (who went out of business in 1955) input of 155,000 BTU, output of 125,000 BTU. The boiler vents alone into a 50 ft brick chimney on the outside wall of the house. The flue pipe is about 10 inches in diameter. The house is on radiator heat with one thermostat on the first floor that controls the two floors of living space. Even though the house is very big, our ANNUAL gas bills, indicate 1100 ccf, mainly because the majority of the time the house is empty and sitting at 50 but years ago when people were home most of the day it runs around 3000 ccf. The largest gas consumption over the past three years was in a January and used ~700 ccf of gas.
According to the guys who measured, they say it's sized right on the money. First guy was a co-worker's brother who owned a HVAC company, now he's retired in Florida. Passed on that opportunity then, now the flooding damaged the gas control valve so might as well replace my monster boiler. New guy is great, but tends to have a "hands off" approach. He seems torn between the Munchkin 140M and a Weil-Mclain Ultra. Prices, installation ease and major options are about the same, according to him. Personally he leans a little toward the Ultra because of the outside temp sensor, inclusion of a wall hanger and long parts/labor warranty but people on this site seem to like the Munchkin. Though when I pressed he did say he installed three times more Munchkins then Ultra's.
Please talk specifics:
(I can handle it, BTW I'm not a fan of 316L SS -weak and not very corrosion resistant)
P.S. Please hurry, it was 35 outside this morning, about 55 indoors. He said if I know by Friday he can have either here by Monday - what a guy!