I'm in the process of removing 5 hot water radiators from my 1917 home to have them sandblasted. I'm hoping to get some advice from the forum in two areas...
#1 -- Though I've completely loosened the large nuts on the supply and return sides of the radiator (see pictures below), the radiator won't budge.
There isn't enough clearance on either side to slide the radiator out of the way. The valve stems seem to extend, and are nested, within the valve itself. Do I need to turn the other larger nut (closer to the radiator fins) to back the valve stem away from the valve? Any advice is appreciated.
#2 -- I've found a shop that will sandblast my radiators, but is there anything I need to be careful/watchful of, in getting this done?
Re: Radiator advice
1.Check below the floor to see if there is a union connection that can be broken so at least one side has some movement, or try lifting one side or the other to see if you can get enough movement to break the connection. I would not try to remove the other big nut.
2. make sure the threads on the radiator are sealed so the sand blaster can't damage them, possibly by installing plugs.
Re: Radiator advice
I would follow JLMC'S advice; if you're still having trouble moving the rad, & the supply riser pipe is threaded steel, use penetrating oil on the lower part of the vertical pipe holding the on/off valve (the part under the floor, if you have access, otherwise dribble some oil down the pipe to loosen the under-floor joint).
Using a large plumbers's wrench (the ones with teeth), slip a piece of iron pipe on the handle for leverage, then grip the vertical pipe near the floor & slowly loosen it just enough to move the rad out & away from the valve & free.
Cast iron rads can be damaged in transit if there is any rough handling.
Cast iron is easily cracked & the pressed on seals can be compromised, causing a leak later on.
If the sandblasting outfit you hired will also paint the rads, it's probably worth the effort.
If you plan to have them painted elsewhere, or do it yourself, check out the Yellow Pages for "Painting Contractors" who also do sandblasting.
The rads can sometimes be sandblasted & painted in situ if a plastic tent is set up in the middle of a room.
The painting co. has a long hose that can reach even in a 2nd floor window.
The newly painted rads can be air pressure tested if you plug one end & insert a schrader valve (regular tire valve) with a psi gauge on it in the other end & pressurize to 20 psi for 15 minutes.
If the needle on the psi gauge drops, you've got a leak.
If a leak is found, brush soapy water or shaving cream around the rad to find the leak; if the leak is a crack, the section will have to be removed, or the rad discarded for a replacement.
If the leak is between a pressed section, it can be re-pressed.
A 1 1/2" black steel pipe can be threaded on both ends & used with washers & bolts to re-press any loosened joint; apply some high heat caulking cmpd first.
Remove the upper and lower plugs, insert the pipe thru the rad & tighten the black pipe till the rad is re-sealed.
Rad connections (plugs, etc.) have been in place for years & can be hard to loosen; soak with penetrating oil overnight if the plugs or fitting won't budge.
High temp caulking compound is avaialble at plumbing supply stores.