Shim Bottom of Radiator? (not legs)

wintermute

My wife and I moved into a nice old house a year ago and I have to admit, the steam system seems to be in pretty good shape. One small problem I'm dealing with now is a radiator in our kitchen that is pitched wrong. The problem is that a slate floor that is younger than the radiator was laid over an existing floor, and to get a shim under the legs, I would have to raise the radiator over an inch to clear the slate floor. Whoever installed the floor did a really good job and there is pretty much zero clearance around the legs. Does it make sense to place a shim directly under the (cast iron) radiator, or is this just causing a potential faliure spot. Thanks.

Hap_Hazzard

Need more information.

How do you know the pitch is wrong? What is the problem you're having with it?



Is this a 1-pipe or 2-pipe system?



What type of radiator is it? (Got any pictures?)



Was the pitch of the radiator affected by the installation of the flooring or has it always been like this, as far as you can tell?

wintermute

More Info

The radiator gets hot just fine, but there is some knocking and the vent bubbles a bit. I checked the pitch using a torpedo level. It's a typical old floor-mount cast iron radiator at the end of a one-pipe system. I doubt the flooring installation affected the pitch, but that section of the house is 200 years old and I think it's due to just typical settlement.

crash2009

Epoxy?

The way I have this pictured in my mind is that the radiator legs are sitting on the original floor.  A new slate floor was added, and now the slate (one inch thick) surrounds the leg.  If you can lift the radiator up, without breaking it or the pipes going to it, is there enough space to pour or inject something?  If so, (and this is just an idea, and I have never tried it)



How about using a two part epoxy, injected with a sringe.  Both are available at your local hardware store.

BobC

Lever

These old radiators are very heavy and usually one uses a 2X4 as a lever to raise it up so you can shim the vent end a bit. You might not have room for a 2X4 but a 1" length of fir or any hardwood should work, then try using quarters to shim up the legs.



Bob

wintermute

More info

Crash, you are correct in the way you imagine it. In response to Bob's post, I've been using a 1"steel pipe as a lever and a 2x2 as a fulcrum. The problem is that I don't have enough play to raise the bottom of the legs above the floor. The clearance is very tight, but the epoxy may work, but I would have to find a long, very narrow syringe to make it through the space between leg and floor.



So I'm assuming that shimming the radiator body itself (that only clears the floor by half an inch) isnt a good idea since no one's commented on that. Or here's a third option: the radiator heats up no problem, the knocking isn't too bad and is nowhere near the bedrooms, and it's venting fine, albeit a little wet -maybe since it ain't broke, don't fix it?

crash2009

Here is

 the model number of the syringes I had in mind.  They might be small enough, only you would know for sure.  Maybe West System has something smaller that would fit for you.

Rod

Shimming

Hi- I'd try shimming up the underside of the radiator first and see if that makes any difference before I went to the hassle doing of a more permanent fix like the epoxy or hard spacers.  I'd also use wide blocks so the weight is spread out of the slate. You just need enough slope to "encourage " the condensate to travel out the inlet pipe. Too much slope can cause problems!  Be careful that the radiator is stable on the blocking.

- Rod

Dave in QCA

Knocking as in?

I am wondering if the knocking that you are hearing is water hammer or if it is simply expansion clinking of a cold radiator.



I had a similar problem of a settled radiator, but it had not settled to bad.  Apparently from previous leaks, the fir flooring around the ends of a couple radiators was a little stained and discolored.  The spots where the feet set were rotted away and the feet were now setting in depressions about 1/4 -1/2" deep.  Since it was a wood floor, I mixed up a little Durham's Rock Hard putty and filled the holes.  Of course, I had to disconnect the radiator and then reinstall it.  Since you have said you don't have much play, you may not be able to do that.



And, at last there is a face to connect with the name.  Crash, the great insulator!   Howdy!

crash2009

Yea Dave, thats me

Can't miss that red and white, aye?  I should paint something blue, now that I am in America.  After you reminded me about moving radiators, I got thinking abour expansion and contraction.  The legs on this one might be mortared in.  If they are how would it expand and contract.  That might make some noise.  Radiators can dig a hole over time, but it sounds like this one is cemented in.  Only Winter would know for sure though, but from the sound of things, the new slate is tight to the legs of the radiator.

wintermute

That's Right Crash

The slate is VERY tight to the radiator legs. To the point that I would not be able to fit your syringe in the depression. The radiator does make the normal "tinking" and "tonking" of an expanding radiator, but every few cycles I get 2 or 3 'Bangs!" at the start of the cycle. If i get the chance tonight, I'll try to raise the vent end of the radiator just to see if I can even lift it without the legs getting caught.

crash2009

The tips of the legs

 might be flared out and under the slate.  If you raise it you might break the tip of the radiator leg.  Also you might chip the slate.  Maybe we should identify what kind of radiator it is.  Can we see a picture?  When you respond to this, Click File Attachment/Browse then look for your camera, select the photo you want to post, then click submit.



You might have to get someone in to disconnect the radiator from the steam before you can lift it.  Then have it re-piped so that it rests above the new slate floor.

gypsy

i created a similar situation...

I tiled my bathroom in stone and instead of re-piping the radiator, i just went around the feet with 1 inch tiles and grout.  (this radiator had also worked itself down into the floor but not quite to the depth yours seems to be... though maybe they who put the slate down used a lot of mastic to level the floor)...  Unfortunately I didnt check to see if the radiator was pitched correctly first...



Not a big deal to fix though, i just popped out some of the grout and tiles on the side that needed to be lifted and slid some coins into the space and under the legs to give it a little pitch and then re grouted and tiled around the feet... worked like a charm... no expansion noises, banging, etc...



you may want to see if you can cut out some of the tile around the legs just enough to get something under the end that needs to be raised up... for slate you could try something like a dremmel maybe... then re grout around them-and the other side which will probably chip in the process.