I have to disagree. I would never go with steam unless the boiler was undersized for the house: And you had other supplimental heat to make up for the shortfall. Here's why:
With steam you get ZERO heat until you raise the water to a boil, no steam, no circulation, not a single BTU into the rooms of the house.
So lets say it is evening, 45* outdoors, Has been a sunny 60* day and the heat hasn't been on all day. Now the house has cooled to the thermostat set point of say 65*. The boiler fires up, gas, oil, propane or coal, doesn't matter, The water is cool or only warm, nowhere near hot. The fire has to run for 30minutes to an hour before there is appreciable steam in the pipes, has warmed all the iron pipes, radiators and warmed the still cooling house.
Think about the amount of heat going up the chimney for 30-60 minutes before there is ANY appreciable heat in the house.
Personally I call that inefficient.
You will burn a huge amount of fuel to warm the house up a few degrees, Then the thermostat will be satisfied, and the boiler shuts down. Then a few hours later, the cycle starts again, 30-60 minutes of fuel burning to add 5* to the house temp.
Now with hot water, the same weather scenario, the thermostat calls for heat, the circulator pump starts, the fire starts or revs up [coal], as soon as the water reaches 130-140*, the house is getting some heat into the rooms through the radiators and baseboard units. The water may never reach the set point of the boiler, which is usually 160-180*. The house thermostat will probably be satisfied much sooner.
As the house sits through the evening, the water in the raditators adds thermal mass to the units, prolonging the heating effect into the room, and the water in the boiler cools just like the steam boiler would, but it will have a much lower temp difference to effect the cooling rate, say 170* water/70* boiler room temp compared to 212* water/not steam vs 70* boiler room temp.
The only way steam is better is if the boiler is small for the house, and runs almost continously, constantly making steam. Then the steam is as good as water, but still not better, except for automatic house humidifying, background sounds [hissing, banging etc].
One pluss I forgot is entertainment, I saw a cat sleeping on a steam radiator when the system started up, when the system did one of it's infamous 'BANGs'right in that radiator. That cat must have leaped 2' in the air, looked like a cartoon cat, hair all fluffed out legs askew, yowling. I laughed for ten minutes.
Maybe a second steam boiler in parallel that can fire up when the weather is really cold to make up the difference?? Don't know, but I certainly wouldn't go back to a one pipe steam setup.
Alexw, have you hooked up a cold air return to the distribution blower of your Poconno stove yet? For about $30 you can fix your heat problem. I would never consider buying another heating appliance till you have tried to fix the problems with the current instalation.
I was able to heat my shop with a LeisureLine Hyfire I, running at about 60%, around 80-85K. My shop has four rollup doors, [not well sealed] only 80% of the walls have R-8 foam insulation, and the ceiling has R-14 foam. The floor heat was off, and cold. I was able to get 60* air temp with the HYfire, the shop is 40'x60'x15' ceilings. just a big drafty box, and it warmed-up fairly well. In a house with any insulation, even just drywall or plaster/ airspace/ outside wall would be better than my shop. My four windows are single pane windows.
Anyway, my take on steam is live with it if you have it, but I'd never reinstall a steam boiler unless it was free and the labor was free,
BTW, I just had friends buy a steam heated older home in an upscale neighborhood, and the heat is eating them up. It is a nice, insulated house, with good windows, but the long burn time, cool down cycle that I describe above is causing huge gas bills, more than their previous house that was 2.5 times as big with forced air heat. I went and visited and watched their steam boiler cycle, and measured the chimney temps. Glad it's not my gas$ bill!! Wish it wasn't my friend's either.
Last edited by LsFarm
on Wed Mar 14, 2007 4:17 pm, edited 2 times in total.