We got our hands dirty last year with coal for the first time replacing our wood stove with a harman mark II and enjoyed warm toasty winter morning with much less effort. However, we still spend a fair amount on oil as our tankless hot water tank is part of the oil boiler and we have to heat a zone in an inlaw apartment to keep pipes from freezing. Ideally a new coal boiler in series or parallel would be ideal, but we have a small basement with little room leftover after the oil tank, boiler, electrical service, sump pump, and electric hot water heater for the inlaw apartment. We also only have one flue in the basement and no good location that I can see to power vent anything (i.e.: windows above only exterior walls to basement)
Our current boiler came with the house. It is a Burnham V-35.http://www.hvacprotech.org/Firedragon/v3.pdf
From what I gather 208k btu/hr net.
So given my current circumstances I think that leaves me looking for a dual fuel unit as I think we need oil for code/insurance/resale value and we need the flexibility to head south during the winter for a vacation and not worry about the care and feeding of a coal unit. I was initially reluctant to go down this road, but it looks like the switchover from oil-coal-oil is relatively easy and doesn't require a licensed plumber to do it.
A local guy had me look at the LL WL110 but it looks like it doesn't have enough net output...or do I need to be looking at apples to apples with a coal unit? During our phone call he talked about the efficiencies of a coal boiler running all the time versus a oil fired unit having to "come on strong" to heat up on demand. Does this make any sense or should I be looking to match BTU for BTU with my current oil boiler?
The EFM 520 seems to come close on the coal side but the oil fired specs are too low. Can that be upgraded?
Can you point me in a direction of which models make sense for me to look at? On another note the height of the unit could be an issue also...We only have about 6' in the basement and with pipes running overhead even less. Occasional pooling of water in the basement also. The current boiler is on blocks and the new ones should also be. Even when the sump pump is working we get some pooling. When they fail...alot.