In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Replacement boiler sizing
I am a new homeowner looking to replace a 50+ year old oil-fired Arcoliner boiler rated at 73 MBH output. The home is a 1400 sq ft cape (unfinished basement not included) with forced hot water convectors in the Boston area.
My question is on sizing. During the last winter, the house would heat up fine but relatively slowly, say 2-3 °F/hour on cold days. I set the thermostat back a good 7 °F or so during the day, so the warm up time was farily significant. I noticed the boiler would fire for a good 30-40 min, turn off for say 10 min while the pump circulated, and fire on again for another 20-30 min. This would repeat 2-4 times while the house got up to temperature.
I have since learned that the first floor was uninsulated, so I had cellulose blown in which should cut down on the heat loss significantly.
One contractor recommended a boiler rated at 84 MBH. Would this now be oversizing? I am unsure because the house took so long to heat up before (which would dictate a larger boiler needed), but with this new insulation and a low-mass, low water content boiler (which would dictate a smaller boiler), I imagine it will be much faster this year. I wonder if I would want to stay at the 73 MBH range or even go smaller. I was hoping to install the new boiler this summer, and not go through another winter to find out how much the insulation helped.
Any advice would be most appreciated!