Old cast iron column radiators flow return-urgent help

[Unregistered]

Hi there

I wondered if anyone could help quite urgently as rads get piped in tomorrow and I have a lot of conflicting advice.

We are restoring an old property at the moment which had no central heating. We are putting in modern combi and old reclaimed cast iron column radiators. Some are quite large. We are using these valves

Premier Traditional Angled Radiator Valves | Satin Nickel | Online Now

Some rads have

inlet at top/ outlet at bottom-opposite ends

inlet at top and outlet at bottom-same end

We were going to pipe: flow in at bottom and return at top as we were told the hold water would rise to the return?

I have since read that putting flow at top is best as water cools it will fall to return? Felling really confused?

I also read that bottom to bottom is ok for flow and return? Aesthetically would prefer this and would avoid us having to plaster in pipes chased in channel for top? Would this be ok if we balance the rads properly. Flow is in 22mm branched in 15mm just before each rad.

Just want uniform heat across the rads? Do you think if we do bottom to bottom and restrict return they will have time to get hot on all the sections?

Any advice very much appreciated
Elli

 

[Elli]

on the JTM website if its described as galvanised is this steel? Are these more hard wearing?

thanks

 

[ShaunCorbs]

so kind of like use the hacksaw to notch the thread that's stuck in then try and sprise it out?

yes but dont cut too far (into rad threads) and cut it top and bottom and then either side and you should be able to work one out then the rest will be easy only prob it takes ages

 

[ShaunCorbs]

on the JTM website if its described as galvanised is this steel? Are these more hard wearing?

thanks

well in your post you said brass the only prob with brass is its soft so might cross thread

 

[Elli]

In galvanized they only have a 'galvanized hollow plug' that has like a square bit on the end-would this be ok?

 

[rpm]

so kind of like use the hacksaw to notch the thread that's stuck in then try and sprise it out?

My method is to two cuts one at 12 o clock and the second at 10 o clock, once that segment is out then hammer & chisel at 12 o clock towards 10 o clock and downwards, this should take the pressure off the fitting and it will come out by hand.

This is for a right is tight thread.

 

[joni os]

When the 10 to 12 piece is removed. I would hammer 1 towards 7 or 9 towards 3 which ever gave the most bite.

 

[rpm]

When the 10 to 12 piece is removed. I would hammer 1 towards 7 or 9 towards 3 which ever gave the most bite.

I wasn`t trying to undo it, more like folding it in towards the centre thus releasing the "grip".

 

[rpm]

Hi everyone, been advised to use LSX sealant when fitting the stop ends-is this the best one do you think?

Wouldn`t use LSX in this application.

 

[stevetheplumber]

These rads are not designed to work at 3 bar pressure which is the safety valve setting on your combi.
They have spent there lives so far in open vented systems with a head pressure of a floor or two i.e. 0.6 - 1bar.

If I were you I would be testing them first as SimonG suggested, then I would fit a safety valve with a lower setting to the system!

BTW - TBOE for the con's

pressure wont be a problem ive had cast rads with 8 floors on them all the big buildings in london originally had cast iron rads

 

[ShaunCorbs]

pressure wont be a problem ive had cast rads with 8 floors on them all the big buildings in london originally had cast iron rads

+1 what do you think the old boilers were made off/ construction

 

[Unregistered]

Thanks everyone-will try the hacksaw method.

The rads have only recently been removed from buildings where I understand they were working but boiler being fitted Sun so will mention about the safety valve as I don't want to ruin (any more!) of them. Is a sealant necessary for the stop ends on the rads or just PTFE and if so whats the best thing if LSX isn't good for this?

 

[ShaunCorbs]

Thanks everyone-will try the hacksaw method.

The rads have only recently been removed from buildings where I understand they were working but boiler being fitted Sun so will mention about the safety valve as I don't want to ruin (any more!) of them. Is a sealant necessary for the stop ends on the rads or just PTFE and if so whats the best thing if LSX isn't good for this?

boss white and hemp

[video=youtube;bFXgwO9qszY]https://www.youtube.com/watch?v=bFXgwO9qszY[/video]

 

[joni os]

boss white and hemp

At times the old ways are the best ways.

.

 

[Ric2013]

boss white and hemp

[video=youtube;bFXgwO9qszY]https://www.youtube.com/watch?v=bFXgwO9qszY[/video]

That paste he's using isn't much like boss white though? The guy in the video seems to think the paste is just for lubrication. Anyone else here tried hemp without boss? It don't seal lol!

I like using Boss and hemp. Makes me feel old-school

 

[ShaunCorbs]

That paste he's using isn't much like boss white though? The guy in the video seems to think the paste is just for lubrication. Anyone else here tried hemp without boss? It don't seal lol!

It's an American vid so will be pipe dope but use boss white instead and apply like vid and it is required