Steam Heating System Efficiency and Non Working Radiators

IrishTCG

Hi, first off if this is not in the correct section, I apologize.

I have been living in my residence for 40 years and have decided to tackle the heating system and make sure it is working as efficiently as possible. I also have 2 radiators that do not operate in the system.

Backstory, I have a one pipe radiator system, originally fueled by a coal furnace now converted to Natural Gas, single zone with an auto fill for water. The home is two stories with 4 radiators on each floor built in the early 1900's with original radiators. After researching, I came across information that when radiators were originally installed, they were all the same size, height wise. I have 8 radiators in total, 5 radiators (originally 7) that are all the same size, 34 inches and 2 that are shorter, 24 inches.

I have read that systems like this were all originally sized the same height but width was dependent on the room size, is this correct?

The furnace is in the rear of the home in the basement centered along the back wall, home is 25ft x 25ft square. There is one steam pipe going from the furnace to the front of the home (25 ft) and 'Tee's' to the right and down for the return (The only radiators with a return) and straight into another T that goes to the left and right with 1 radiator on the first floor (Foyer) to the right (3ft) of the T, branching off to a vertical run to another radiator directly above (Bedroom 3) and from the T in the basement 10ft to the right, with a radiator on the first floor (Living Room) and branching off to a vertical run to another radiator on the second floor directly above (Bedroom 1). All 4 of these radiators were 34 inch's with 7 fin, with bullet style vents.

The first floor radiator to the right (Foyer) was replaced about 10 years ago for a baseboard fin radiator, a mistake in my opinion as it does not really heat up or mostly just spits water out of the vent. I replaced all the shutoff valves on the system about 15 years ago and replaced some of the vents with adjustable vents. The second radiator, which is an original, spits out of the vent, so much so I have quite a bit of wall repair to deal with. Before a renovation, I noticed this never did this.

Is the smaller radiator causing too much pressure on the other radiators? Besides trying to find a replacement 34 inch radiator, should I replace the vents with the original bullet style? I noticed that when I originally replaced the vents, the old ones had a curved stem that went deeper into the rad where the new style does not have. Would it be common that only these radiators would have a return, or is it an indication that these were 'original' and the others at the back of the house were added later?

Now for the back radiators. Off of the long steam pipe, it T's off to against the back wall of the house. The top of the T has the main vent. Once the secondary steam pipe reaches the back wall it T's to the right and left. To the right of the T, it goes into a 24 inch 7 fin radiator (Kitchen) and branching off to a vertical run up to a 34 inch 2 fin radiator (Bathroom). From the T in the basement 10ft to the left, with a radiator on the first floor (Dining Room) and branching off to a vertical run to another radiator on the second floor directly above (Bedroom 2), this radiator was 24 inch 10 fin.

The first floor radiator to the right is always the hottest in the home as it is directly above the furnace. The other radiator on the first floor in this run is an original 34 inch 7 fin (Dining Room), this radiator spits out of the vent (new style adjustable). On the second floor, the original bathroom radiator was replaced in a remodel 15 years ago and was replaced with a similar baseboard steam radiator. The bathroom radiator has never worked even with a valve and vent replacement. The last radiator (Bedroom 2) was reduced to a 7 fin radiator and turned, this is always extremely hot and commonly has it's valve turned off.

Would I be wise to replace all the small radiators with the original size radiators? Do you think this, with replacing the vents to the old style bullet would help, or are my heating issues much deeper? Do you see an issue the back radiators do not have a separate return? Also, the steam pipes in the basement are insulated (wrapped with asbestos, I believe [pending removal]). Should the return be insulated?

Thanks for reading the long post and any help/advice you can give.

Steamhead

First thing to do is get a Steam Man in there. Where are you located?

ethicalpaul

Yeah that’s a lot to unpack and comprehend via the written word. I agree with @Steamhead

Jamie Hall

Indeed ^^.

However, a few comments -- first, replacing the radiators or changing them -- except for the baseboard one, which is always problematic with steam at best -- won't make much difference in operation. Now if they all heated evenly, and some rooms were way too hot, you might consider changing for a smaller one there, but it's much easier just to change the vents.

Second, is there any hammering in the system? Water spitting out of vents is often a sign that either the radiators are pitched wrong or that there are places in the piping which are pitched wrong. You could look for that -- remember that any water that gets into the steam lines (condensate) has to be able to flow back to the boiler easily.

Third, another possible problem with spitting vents is that the boiler may be operating at too high a pressure. Check the pressure control device to see what pressures it is set at (post a picture of it, if you need help with that.

Fourth, another possible problem is that the near boiler piping is not correct. Pictures of the boiler will help with that.

But, as @Steamhead and @ethicalpaul both said -- your best bet is to get someone qualified in steam heat out there to look at the system.