Old cast iron rad, built to last or asking for trouble?

[Tirglas_7]

Hi

Continuing with my house refurb, I'm now close to completing the lounge.

I have an old cast iron rad I was given, unknown where it originates from or whether it is sound (visually ok).
910x560x145mm

IMG_20200717_102227

• Tirglas_7
• 17 Jul 2020

IMG_20200717_102303

• Tirglas_7
• 17 Jul 2020

If I flush/back flush it thoroughly, then use a hydraulic pressure tester at 1.5 times system pressure, would that be enough to be confident in it?

If it passed I'd then strip the paint, prime and paint.

Not sure what size the fittings I'd need, anyone know what kind of sizes reducers/adapter I'll likely need?

Any other info or advice?

Thx in advance

 

[Madrab]

Yes, these rads need pressure tested to ensure they aren't porous. I'd be tempted to take the pressure up a little higher, say up to 3-4 bar.

It depends on the tappings but you do get adapters etc design specifically for CI rads. Another trick I do is add an amount of inhibitor directly into the rad to ensure it is coated as it's being filled.

 

[Bodd]

Is it worth testing that high if its on a gravity system.

Give it a good clean test then paint then fit... Why not.

 

[Madrab]

Is it worth testing that high if its on a gravity system.

It's more to test the integrity of the cast and joints/tappings for corrosion/thinning/pinholing rather than can it actually handle the system pressure whether it's gravity or sealed. That confirmation would just be a side effect of the test.

 

[Bodd]

Fairs doos

 

[HERTS P&D]

I got one off ebay and pressure tested it with my jetter, I did go well over 4 bar.



Andy

 

[Madrab]

I did go well over 4 bar.

Nothing better than a good severe stress test

 

[muggles]

Worth putting it in position before pressure testing if you can, as moving them can stress the joints and cause leaks

 

[Tirglas_7]

Thanks for the replies guys.

Had a go at unscrewing one of the blanks, you guessed it its not moving.

Any tips on getting the original tappings/blanks out? Is it worth investing in a set of 24inch stillsons? What about heat from a heat gun or soldering torch?

Doubt they've been out in a long long time, are they potentially corroded in and never coming out?

 

[muggles]

Yes you could heat it up and put a big spanner on it. One end will be standard thread, the other will be left handed, IE clockwise to unscrew

 

[Tirglas_7]

OK thanks

Is there anyway of telling which is which with them installed?

 

[Tirglas_7]

Lh or Rh I mean

 

[Madrab]

are they potentially corroded in and never coming out

Yup, more than likely, I would avoid trying that as you may end just breaking things, it's been in there a long time.

Why do you want them out anyway? Only ones you may need out are the bottom valve tails to get some newer ones in.

 

[JimCrow]

Yes you could heat it up and put a big spanner on it. One end will be standard thread, the other will be left handed, IE clockwise to unscrew

Only the internal nipples joining the sections on those rads have R/H & L/H threads, the valve, air vent and plug tappings are standard BSP.

 

[Tirglas_7]

Yup, more than likely, I would avoid trying that as you may end just breaking things, it's been in there a long time.

Why do you want them out anyway? Only ones you may need out are the bottom valve tails to get some newer ones in.

I want to have the inlet & outlet on the bottom, at the min it has one at the top and one at the bottom unfortunately