Locating hot water cast iron piping

psgstl

I have a large bedroom with sitting area with no radiator(s) on 3rd fl of my 1905 house. This room faces north along with a large walk-in closet with no radiator. On south side are 3 bedrooms, all of which have radiators. At the end of the hallway to the east is a bathroom with a radiator. All of these radiators appear original.

This room has not yet been renovated and has painted floor. I have carefully examined the entire perimeter, looking for patches/replacement boards where radiator might have been. The logical location would have been under 2-sets of windows on north wall with 8 ft space, but no evidence found. Since entire basement ceiling is lath and plaster, do not know if original supply/return piping might be there.

With system running at 170F, I would like to see if any heat is detected under the floor in this room, assuming original piping might have been capped.

Does anyone have first-hand experience performing this task and with what instruments? I suspect a professional grade thermal imaging device would have the best chance of success. How about a metal detector that would filter out all of the nails? Seeking advice and suggestions.

Thanks, John

EdTheHeaterMan

This sounds like a difficult proposition.  You may be able to find something with an infrared camera.  

You may also be able to add a zone that is independent of that original system.    PEX tubing with an oxygen barrier can easily be snaked between walls and through closets and floor joist to get from the basement to the attic floor.  Electricians do this all the time for wires, and since you will need a wire to connect the zone thermostat, you may ask the electrician friends you have if they can help you get those PEX pipes in place for you.  

Then you can use any type of radiator in order to get the comfort you are looking for.  You won't be limited to matching the radiators for the new section with the old section.

psgstl

Thanks, Ed for the suggestion. Last week, found a disconnected 32 section Rococo which matches other units.

It is only 18 inches tall but may decide to use it anyway.. pressure tested it over the weekend…all is good.

bburd

The radiator should be sized to the heat loss of the room.

pecmsg

it wasn’t uncommon to NOT heat the 3rd floor.
the 1st and 2nd supplied minimal heat.

Big Ed_4

I would assume the third floor was the attic when the home was built ( tax reasons). And the original central heating system heated the first two floors . ..

Jamie Hall

An infrared camera does sound attractive — there are some pretty cheap ones which clip onto smartphones — but… since there is no radiator in that space, there will be no circulation in any old pipes, and thus no signature. A good metal detector, though, might work very well.

On the other hand, it's likely that there never was radiation up there. And, as has been said, with some ingenuity and some help from electricians who do this sort of thing from time to time you may be able to get PEX over there without too much hassle — and minimal intrusion. May I suggest, though, going in through the third floor floor, rather than through the second floor plaster and lathe ceiling? It is much easier to make a satisfactory patch in a wooden floor than it is in a hard plaster ceiling (or wall, for that matter!) unless you yourself are good at it — or you know someone who is. Don't even think of a drywall patch, though — if you do it, do it right.

EBEBRATT-Ed

Look for closets on floors 1 & 2 that line up with each other. The other spot is near the chimney you can usually snake pex up there.

And with a 1905 house you could well have balloon framing in the outside walls & maybe the inside walls. I dropped a string from the second floor with a weight on it and found it on the basement floor.

But you probably don't want pex in an outside wall.