Radiator replacement

avidrissman

In my other post, several posters were not thrilled to see my radiator setup in my apartment, and called out several issues with it.

You’re right. I’m working through a plan to fix it, and want to run it by you folks.

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The current setup dates back to a reno. We removed the drywall and exposed the brick, and all of the wiring that was in the wall was routed through a box at the bottom of the wall. That box is not wide enough for the cast iron radiator to sit on. Therefore, after several rounds of wild incompetence, the contractors placed most of the radiator feet on top of cheap wood blocks on top of the box, leaving some unsupported.

After reading the other post, I’m actually angry at myself, because at the time I knew that it was a hack job, but I let them get away with it because it was after five rounds of idiocy, and I wanted this to just be done. My mistake.

The problem that I have is that the box is not stable enough or wide enough to hold a cast iron radiator, so my best option seems to be wall-mounting.

Option #1:

Use OCS BWH1 hangers on my existing radiators (which I believe are OCS 4×19s). Pros: Radiator reuse. Cons: I think my wall is stable enough, but I’m not sure. I think my living room radiator is bent under its own weight and I’m not sure I want to keep it. Hanging a radiator that has feet seems silly.

Option #2:

Get new OCS footless radiators, hang them with the BWH1 hangers. Pros: New radiators. Cons: New radiators. Questions of stability.

Option #3:

Get new Charleston Pro steel radiators. Pros: They’re light and meant to be mounted on the wall. Cons: Capacity.

My current cast iron radiators are

Living room: 4×19×38, 14,500 BTU/h
Bedroom: 4×19×18, 7,000 BTU/h

All the standard sizing tools agree on those sizes, but the Charleston radiators simply don’t have that capacity. I have windows that force me to use the 16″ version, so I would need to get:

Living room: 16″×72″, 8,970 BTU/h
Bedroom: either 16″×36″, 4,370 BTU/h or 24″×24″, 4,654 BTU/h

Those radiators have significantly less heating capacity, but the reality is that during the winter I very often shut the valve on my bedroom radiator because the room is too hot, and I have a TRV on my living room radiator to try to hit a reasonable temperature. So I’m thinking that the capacity drop will be OK.

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The plan then would be, in the summer:

1. Have a plumber unplumb the old radiators.
2. Have a handyperson help me mount new Charleston radiators on the wall, properly tilted, well off the box.
3. Carefully cut away the flooring from the inlet pipes and put an escutcheon on them.
4. Have the plumber plumb the new hanging radiators.

Am I missing anything plan-wise? Thanks.

lockdown_lou

I have some Charleston Pro radiators.  Two 16x72 in the (large) bedroom with 10 windows,  and two in the bathroom.  Both work really well. 

Beware, however that they rarely heat up all over.  Since the vent is at the top and the sections are connected at the top,  only the top half of the radiator gets really hot before the vent closes.  Not sure if the radiation calculations take that into consideration. 

avidrissman

lockdown_lou said:

Beware, however that they rarely heat up all over.  Since the vent is at the top and the sections are connected at the top,  only the top half of the radiator gets really hot before the vent closes

That’s interesting. A lot of radiators are designed that way, though. How is that avoided in the standard cast-iron ones?

bburd

avidrissman said:

Beware, however that they rarely heat up all over.  Since the vent is at the top and the sections are connected at the top,  only the top half of the radiator gets really hot before the vent closes

That’s interesting. A lot of radiators are designed that way, though. How is that avoided in the standard cast-iron ones?

There is a second vent tapping, usually about 2/3 of the way down the side of the radiator, used for steam.

mattmia2

You can hang either from the brick if you use the right anchors. the cast iron will heat and cool more slowly so the heat will be more even than the steel. I wouldn't be too concerned about hanging a radiator with feet. You could change the sections to end sections without feet as well.

Jamie Hall

lockdown_lou said:

I have some Charleston Pro radiators.  Two 16x72 in the (large) bedroom with 10 windows,  and two in the bathroom.  Both work really well. 

Beware, however that they rarely heat up all over.  Since the vent is at the top and the sections are connected at the top,  only the top half of the radiator gets really hot before the vent closes.  Not sure if the radiation calculations take that into consideration. 

If this is steam, and the vent is at the top, it's at the wrong place. As @bburd said, there is a vent tapping, for use when the radiator is used for steam, about two thirds of the way down on an end section. Use that one.

lockdown_lou

Jamie Hall said:

I have some Charleston Pro radiators.  Two 16x72 in the (large) bedroom with 10 windows,  and two in the bathroom.  Both work really well. 

Beware, however that they rarely heat up all over.  Since the vent is at the top and the sections are connected at the top,  only the top half of the radiator gets really hot before the vent closes.  Not sure if the radiation calculations take that into consideration. 

If this is steam, and the vent is at the top, it's at the wrong place. As @bburd said, there is a vent tapping, for use when the radiator is used for steam, about two thirds of the way down on an end section. Use that one.

I hear you, but Charleston Pro rads don’t have a steam tapping to my knowledge.  Only at the top. 

It’s not that bad,  but if you spec them for steam it’s worth mentioning.  They get sizzling hot on the top half for sure, and during a long heating cycle work really well.  

mattmia2

you could rig up something to block that top connection to the last section so the steam has to go down to get to the vent

dopey27177

Looking at this radiator, it appears to be for water heating or two pipe steam This is two tube radiator and may not be adaptable to relocate the vent valve.

Jake

avidrissman

https://steamradiators.com/install-ct.html shows a one-pipe steam installation, so they support it installed like that.

mattmia2

What if you put the vent in the bottom tapping, especially if you used an eccentric reducer or you turned a plug in to an eccentric reducer? You could also use a 3/4" ell and a 6" or so nipple to help it separate any condensate the air is trying to bring with it.

dopey27177

do not like the vent on the top tapping. better there tan the bottom tapping where condensate and rust can damage the vent valve. The radiator is quite long so you should not have much of a problem with heating.

A fix is possible if you want to do it.

Take out the plugs from both the top and bottom of the radiator.

Install bushings tapped to 1/2" in top and bottom at the far side of the inlet section.

In the bottom tapping install a 1/2" nipple and elbow looking up, in the top tapping install a nipple and elbow looking down.

In the top elbow looking down install a 1/2 by 6" nipple and 1/2 by 1/8 T OR 1/2 BY 1/4" T, with a 1/2" nipple. In the bottom elbow install a cut pipe and union, connect to the upper nipple. Now install your 1/8" vent valve or 1/4" vent valve if that is what you desire.