Corto Cast Iron radiators, parts available?

[goosegunner]

I ended up buying 12 Corto cast iron radiators.

Does anyone know if they can be repaired if they have leaks?

Can they be separated and put back together with new bushings if needed?


I got them for $25 each so I don't have lot in them at this point. If they don't work out they will be sold or scrapped.

560 EDR total.

gg

 

[Singed Eyebrows]

I ended up buying 12 Corto cast iron radiators.

Does anyone know if they can be repaired if they have leaks?

Can they be separated and put back together with new bushings if needed?


I got them for $25 each so I don't have lot in them at this point. If they don't work out they will be sold or scrapped.

560 EDR total.

gg

I do not believe there are any gaskets etc in these. All the ones I have & have heard of use push nipples that are accurately machined. If they leak, brazing is the way to go for repairs. Grind a V groove in the crack & use braze rod & oxy/act torch with CAST IRON flux. If done carefully its as good as new, Randy

 

[goosegunner]

I ended up buying 12 Corto cast iron radiators.

Does anyone know if they can be repaired if they have leaks?

Can they be separated and put back together with new bushings if needed?


I got them for $25 each so I don't have lot in them at this point. If they don't work out they will be sold or scrapped.

560 EDR total.

gg

I do not believe there are any gaskets etc in these. All the ones I have & have heard of use push nipples that are accurately machined. If they leak, brazing is the way to go for repairs. Grind a V groove in the crack & use braze rod & oxy/act torch with CAST IRON flux. If done carefully its as good as new, Randy

Can that be done at a joint if that is leaking? Just go around the joint?

Or is it just for holes?

I do remember reading somewhere that JB weld works but brazing sounds like a more solid fix.

gg

 

[Singed Eyebrows]

I ended up buying 12 Corto cast iron radiators.

Does anyone know if they can be repaired if they have leaks?

Can they be separated and put back together with new bushings if needed?


I got them for $25 each so I don't have lot in them at this point. If they don't work out they will be sold or scrapped.

560 EDR total.

gg

I do not believe there are any gaskets etc in these. All the ones I have & have heard of use push nipples that are accurately machined. If they leak, brazing is the way to go for repairs. Grind a V groove in the crack & use braze rod & oxy/act torch with CAST IRON flux. If done carefully its as good as new, Randy

Can that be done at a joint if that is leaking? Just go around the joint?Yes, brazing can be used at a joint as there is very little expansion there. Its important that you grind the cast iron. Cutting tools are not suitable for surface prep. JB Weld should work on everything, although you might have difficulty with the joint. Randy

Or is it just for holes?

I do remember reading somewhere that JB weld works but brazing sounds like a more solid fix.

gg

 

[woodsmaster]

Have you pressure checked them yet. I find some fittings and check them one at a time and see what you got. pump them
up to 60 psi and let it sit over night and see if the pressure drops any be sure to check your connections with soapy water.

 

[goosegunner]

Have you pressure checked them yet. I find some fittings and check them one at a time and see what you got. pump them
up to 60 psi and let it sit over night and see if the pressure drops any be sure to check your connections with soapy water.

No I have not checked them yet. The first four I got were just taken out of service as steam heat. I got those for $20 each and they are 48 EDR and one is real big at close to 80 EDR.

I will be working on them this spring summer, just trying to get details about restoring at this point.

Of the remaining 8, Seven look good with no signs of drips. One does have a hole in it. They had to be purchased as a lot so that is how I got the one that is bad for sure.

gg

 

[goosegunner]

Any tricks for getting plugs and fittings out of 60-80 year old radiators?

They all have top and bottom ports both ends.

gg

 

[leeeallen]

I spray the fittings down with PB Blaster for a week. Lay the unit down on a piece of cardboard, Then use a 3 ft. pipe wrench with a piece of pipe for leverage. Have some one stand on the rad if necessary. The fittings will either spin out or they will break. If they break, carefully use a chisel to take the fittings out in pieces. Don't mangle the treads.

 

[goosegunner]

I spray the fittings down with PB Blaster for a week. Lay the unit down on a piece of cardboard, Then use a 3 ft. pipe wrench with a piece of pipe for leverage. Have some one stand on the rad if necessary. The fittings will either spin out or they will break. If they break, carefully use a chisel to take the fittings out in pieces. Don't mangle the treads.

Thanks

I was thinking heat but I will start spraying them in advance to loosen things up.

gg

 

[Whitepine2]

I spray the fittings down with PB Blaster for a week. Lay the unit down on a piece of cardboard, Then use a 3 ft. pipe wrench with a piece of pipe for leverage. Have some one stand on the rad if necessary. The fittings will either spin out or they will break. If they break, carefully use a chisel to take the fittings out in pieces. Don't mangle the treads.

Thanks

I was thinking heat but I will start spraying them in advance to loosen things up.

gg

Heat will be needed cast will expand easy. Don't force too much if they don't give up and the plugs are cast (usually are) you can drill the center and keep enlarging the drill hole
then with a cape punch and or drift punch break away the outside of the plug.I tried brazing but found the cast was thin and of course old so it is difficult to do I ended up using the JB weld worked for me. The sections can be taken apart and the nipples can be cleaned,if you have trouble with leaks you can drop a section this will give extra parts the only thing
you will need is threaded rod to make new clamps to pull the sections together and or if old rods are good cut the end off and use die to cut new threads. It's a good idea to run a pipe tap in any of the plug holes and use rector seal on replacements. Good luck
Whitepine2

 

[Clarkbug]

Check out this link:

http://www.masterplumbers.com/plumbviews/2003/old-radiator_QandA.asp

There is a number there to call for getting parts. Ill bet they can help you out with what you need!

 

[goosegunner]

Thanks for the info!

gg

 

[heaterman]

Good advice so far on the PB (that stuff works) and the heat. Ditto the 36.

One method of last resort is to slice through the fitting with a fine toothed metal blade in a sawzall. Cut crossways to the threads in a couple spots about 45* apart, being very careful not to get deep into the thread. Don't cut straight up/down but rather, keep your saw blade tipped toward the outer diameter of the fitting. You want to be able to knock the small section of the fitting (usually a bushing) out of the thread. Then using a punch, tap it lose. Once that's done the rest of the fitting will spin right out. Use Loctite 55 thread cord on the threads of the new fitting going back in and give it a dab of your favorite pipe dope.

CI rads are so versatile and produce extremely comfortable heat, both convective and radiant. I'm designing a new/old system right now which uses a TRV on each of the rads. This will allow room by room temperature control and the beauty of it is that the system will never be "off". The TRV's simply throttle the flow in each rad according to the load in the room. Each rad will be piped back to a common supply/return manifold and a single Wilo V/S circ will run all 7 of them. You want really low flow through a rad to allow natural convective rise/fall of the hot water internally.

PS....if only 6 of them turn out to be in good shape you still got a deal. I have seen large (20 section+) go for $350 around here.

 

[goosegunner]

Would one 42 EDR radiator heat a 14x16 bedroom in a 14 year old house with r19 walls and r38 ceiling with good windows? We use -15 for design temps.

If so how low of water temps would work?

gg

 

[benjamin]

2nd everything so far.

Before you go honking on a fitting, make sure it's right hand threads, especially the radiators that are held together by reverse threaded nipples might have left hand threads on one end at the top. You don't need to use the top holes for connections, you just need to be able to vent them, and you can drill and tap them easier than taking out the threaded plugs.

For broken fittings, I usually prefer the sawzall method, but you can also weld a bead or two the length of the threaded portion, it will soften and expand the metal so that the part under the bead shrinks when it cools, making it much easier to remove. The weld doesn't have to stick to the cast iron, it's the heating that matters.

 

[goosegunner]

So what is the preferred connection points for cast iron radiators.

Straight across the bottom?

8 of the radiators were piped one top and opposite bottom.

4 were piped one pipe steam with on bottom connection. Those have a top plug with a tiny hole for vent, so it will have to be removed.


I thought I would have to remove all four plugs to flush good but that sounds like it might be a bad idea.

gg

 

[benjamin]

You want really low flow through a rad to allow natural convective rise/fall of the hot water internally.

.

Across the bottom works fine, I thought that's what heaterman was saying. If you have to remove a fitting anyway then I'd say it's a matter of preference whether you go across the bottom or top to bottom, or maybe it depends on what fits where you have to install the radiator.

I wouldn't worry about getting all of the gunk out, because you never will. If you see how much casting sand is still inside the crankcases of some old engines you won't worry so much about your radiators.

 

[heaterman]

Would one 42 EDR radiator heat a 14x16 bedroom in a 14 year old house with r19 walls and r38 ceiling with good windows? We use -15 for design temps.

If so how low of water temps would work?

gg

42EDR =

2740 @ 130*,
3780 @ 140*,
4620 @ 150*,
5460 @ 160*,
6300 @ 170*,
7140 @ 180*

So as always......it depends. What's the heat loss of the room?

Off the cuff I would guess that it would be in the range of 20-22 btu/sq ft. provided windows are average size and you don't have two exposed walls. That is a W.A.G. only and no substitute for a heat loss calc.

AFA piping location goes, the only one to avoid is bottom/top on the same side.

Rinse them out as good as you can with a hose and call it good. You will never be able to get them spotless inside. Remember that at very low flow the chunks tend to stay in the radiator. If in doubt install a strainer in your system and check occasionally.

 

[goosegunner]

Wow 4,480 btus at 20/ sq ft, I would probably need 2 of the 42 EDR radiatrs in a 14X16 bedroom to heat it with any low water temps from storage.

Granted that is design temps so average would be much lower, lately I have been averaging 15,000 to 20,000/hr for the whole house, 2850 finished sq ft.

The room has 2 outside walls
also two windows
A 4'x6' window and a 4'x4' window

gg

 

[heaterman]

Wow 4,480 btus at 20/ sq ft, I would probably need 2 of the 42 EDR radiatrs in a 14X16 bedroom to heat it with any low water temps from storage.

Granted that is design temps so average would be much lower, lately I have been averaging 15,000 to 20,000/hr for the whole house, 2850 finished sq ft.

The room has 2 outside walls
also two windows
A 4'x6' window and a 4'x4' window

gg

W = wild

A = a$$

G = guess

If you want to do it right, do a heat loss. Then you'll know.

 

[goosegunner]

Wow 4,480 btus at 20/ sq ft, I would probably need 2 of the 42 EDR radiatrs in a 14X16 bedroom to heat it with any low water temps from storage.

Granted that is design temps so average would be much lower, lately I have been averaging 15,000 to 20,000/hr for the whole house, 2850 finished sq ft.

The room has 2 outside walls
also two windows
A 4'x6' window and a 4'x4' window

gg

W = wild

A = a$$

G = guess

If you want to do it right, do a heat loss. Then you'll know.

I wasn't questioning your WAG, I trying to imagine how and where I could put them in my house. They will most likely end up in garage and out building.

It's probably a lost cause for house anyway because we have a 26'x 36' open floor plan living room,dining, kitchen with 12' cathedral ceilings. With lack of wall space it is hard to imagine finding space in that area for radiant. Under floor is not an option as it is finished ceiling in the basement. I could do one of your fireplace walls with tubing behind stone....or maybe replace my wooden banister with a Long panel radiator.

 

[woodsmaster]

You can get a lot more btu out of the panel rads for less space loss. You have to get the double panel double convectors for
high output, and of course they are more money.