Down firing

Maud

BTU 112K . 60+ year boiler, good condition 225/180K. One burner disabled originally 300K. The pickup calculation gets to 149K and the input from removing another burner is 150K. My interest isn't economic. I don't think out heating cost are intolerable but if I can do my part to reduce unnecessary energy usage I will try. Good window and attic insulation already. Would uneven heating of the boiler is only heated in the middle have a detrimental effect?

MaxMercy

Maud said:

Downsizing

If you're talking about downsizing in the context or replacing the boiler with something modern, then yes - downsize to fit your radiation.

EDIT: I see you edited to down firing. In that case ....

If you're talking about downsizing the burner(s) in the boiler, then probably not. You can only downsize to a certain point and then the efficiency swings back the other way.

Steamhead

@Maud , is this a steam or hot-water system? What make and model is the boiler?

Maud

Two pipe steam , American Standard pre ~1965

EdTheHeaterMan

So there is the possibility of perhaps plugging one of the orifices on the last burner, but I would need to look at the burners. Can you post a photo of the burners with flames? I would not do more than one burner at each end. So depending on the amount of burners you have, that may or may not be a large enough percentage of the total.

Second, I would not downsize more than 12% of the total input. Think of boiling a 4 gallon pot of water with the flame of a candle. Not going to happen, but you will burn lots of candles. So the size of the fire needs to be able to boil the water in the boiler in a reasonable amount of time. If you reduce the flame too much, then you may be less efficient, burning 50,000 BTUs for an hour and not getting any steam is less efficient than burning 100,000/Hour but getting steam in 3 minutes and then shutting down in 17 minutes then staying off for 40 minutes, will use 1/3 less energy every hour and you will be comfortable with hot radiators.

There is a point at which you will have the most efficient use of a fuel, the problem is that the point at which that happens, is different every day based on the outdoor temperature, the construction of the building and the system you are using to heat the home. Then there is the problem that the venting gas temperature may end up being too low and causing condensation of flue gasses which can destroy a chimney or the actual metal in the boiler. This is rare on steam boilers but when you mess with the original design you don't know what can happen. So I would think long and hard on what your modifications might end up doing in the long run.

Maud

Vent gas Temperature is > 400. There's the.. boiler has lasted this long don't mess with it. On the other hand could it have been tweeked and improved for all this time. A new smaller boiler would have a smaller tank as well. Down firing with original tank size might have an unknown effect. If only the two middle burners are running is the tank heating unevenly? https://imgur.com/veUOggv

Steamhead

Maud said:

Two pipe steam , American Standard pre ~1965

@Maud , there is typically a lot of room for efficiency improvement on steam systems, none of which has anything to do with the boiler. I'd bet you have a Vapor system, which is a subclass of steam, and was the Cadillac of heating in its day. Post a few pics of some radiators and we can tell you for sure. Also, tell us where you're located- we might know someone who can help you.