Oil to coal?

Redpoint

I have a 5000+ Sq ft house that was built in 1917 with a vapor vacuum heating kriebel system. The oil boiler is maybe 6-7 years old and is a sc/sct-07-w/s peerless boiler with a riello burner "40". I have a large coal bin right beside the boiler. What I want to do is set up a system with two boilers; the one I have now (oil) for early fall and late spring and a new coal fired boiler to use from nov through march. I want to burn rice coal in an auger type system . Also I already have an indirect system for domestic hot water. Does anyone have any suggestion on if this is a good idea or comments? Thanks

Jamie Hall

Comments...

a) I'm sure it can be done, if you can find an appropriately sized,  modern coal boiler.  I'm not so sure about that.

b) coal is messy

c) the set up and piping for dual boilers is tricky, and best left either to someone who's been through the process (e.g. Vaporvac, here on the Wall) or a really really good pro, and there are a couple of them here on the Wall as well.

JStar

Coal

My first concern is the ability to control the steam pressure of the coal boiler. It can't be done electronically. You'll need to mechanically control the draft to the fire. That's the way the vapor system used to operate.



The most important part of this project, as Jamie touched upon, is to contact somebody from here. Don't try to hire a contractor who "works on steam sometimes". You'll save yourself a lot of trouble by having the system engineered perfectly from start to finish.

Jean-David Beyer

Does anyone have any suggestion on if this is a good idea or comments?

I am a homeowner, not a heating professional.



I think that unless you have unusual circumstances, it is a terrible idea.

My father owned a house that had a coal-fired furnace that the former owner converted to forced air. It had a thermostat in the plenum that turned the blower on if the air in there got up to some temperature or other, say 250F, and turned the blower off if it got down too low, say 150F. It also had a thermostat in the house, and if the house got too cold, it opened the damper in the ash pit of the furnace and closed the one in the vent pipe to the chimney. If the house got warm enough, it closed the one to the ash pit and opened the one to the chimney. It worked pretty well for such a system.



Back then, coal was from $4./ton to $7/ton and it was pretty good coal (anthracite: no smoke). We had a coal bin that was filled once or twice a year and took most of a dump truck of coal at a time. And we had to take the ashes out almost every day and put them into large galvanized garbage cans and carry them upstairs to street level and out to the curb. A year or two after WW-II the city stopped collecting the ashes, so he put a conversion gas burner in. No idea what the efficiency of any of that was.



I happen to know that coal costs a lot more now. I do not know how much, but it could easily be over $100/ton. The EPA or your state DEP may also have regulations about burning it (not just the CO2, but also SO2, arsenic, mercury, etc.). And you may have difficulty disposing of the ashes. You sure would not want to dump it anywhere near an aquafer.

EBEBRATT-Ed

Google

Google EFM Electric Furnace Man. They have a coal boiler. I would think that with the electronic controls and damper actuators available now you could get better control than in the past.

As far as being messy and any environmental issues................??

nicholas bonham-carter

Mixing coal with gas

If you have 2 separate boilers, then the important part of installation is--keep the waterlines at the same height.

In addition, the header should be common, and very big, so as to equalize the pressure between the active boiler, and the inactive. Too much back-pressure on the header will force water from the active to inactive boiler.

Unless you live next to a railway line where the coal trains run, and spill their loads so pickup is free, I would think long and hard about this method of heating.--NBC