I am getting a new boiler with indirect water heater this season. I live in MA, cold climate, in a 2100 sq ft old hse, new insulation and great new windows. I am looking for high efficiency in my new system and as low cost as I can get away with, but w/o cutting corners that I'll regret in the future.
I am weighing two bids from two trusted contractors. Contractor A (promoting Burnham) is giving me a heat loss calculation and B (promoting W-McL) is giving me a heat load calcultaion. B's is lower by a lot.
The particulars: the Burnham unit is the MPO147 (the 115 is not yet available) with the AL50SL water htr and the W-M is WPGO-3 w/ the Super Stor 45 water heater. The MPO147, while bigger, is a triple pass which I like, and higher efficiency. I'm told if the nozzle is reduced on the MPO147 to 85 w/ a higher pump pressure, I may also get as low oil consumption as on the W-M. Sound likely?
The net BTU output for the Burnham is 112K and for the W-M is 100K. Burnham also makes the MPO115, but it's not available yet around here - with a net of 85K BTU.
is it worth going with the more expensive and higher BTU output Burnham 147?
Will I use more oil in the long run with the Burnham MPO 147 than with the W-M?
Does anyone know when the Burnham MPO 115 will be available in the northeast?
Thank you so much in advance for any time you put into answering this long winded question!