Refurbing old rads

[DaveWebb]

I'm planning to take off all my old radiators, which I think have been running for ages without any inhibitor, hose them through in the backyard and restart the system as clean as possible and with loads of Fernox. If i buy new rads they most likely won't fit and i'll end up adapting all the pipework while spending money.

So my question is, is there a product i can use to treat the inside of the rads while i do this? I'm thinking down the lines of Kurust, which i've used on my camper, but swilling that through everything would cost a fortune. Just wondering if anyone has any bright ideas?

Thank you all, Dave

 

[Wayners]

Fill with white vinegar at 6% acidity maybe.
Should work.

As for new rads not fitting. You can get adapters to make up gaps if you don't want to alter pipes

 

[DaveWebb]

Thanks - this looks like the best bet, and dilute a bit

White Vinegar 5L Acetic Acid 20% 4 x Stronger Than Regular Spirit White Vinegar Cleaning for Sanitising & Cleaning - Deodorises & Removes Grime Descaler (4, 5L) : Amazon.co.uk: Grocery

White Vinegar 5L Acetic Acid 20% 4 x Stronger Than Regular Spirit White Vinegar Cleaning for Sanitising & Cleaning - Deodorises & Removes Grime Descaler (4, 5L) : Amazon.co.uk: Grocery

www.amazon.co.uk

 

[DaveWebb]

Any reason not to go stronger?

 

[Harry Bloomfield]

I'm thinking down the lines of Kurust, which i've used on my camper, but swilling that through everything would cost a fortune. Just wondering if anyone has any bright ideas?

Kurust, is simply an expensive form of Phosphoric acid.

You can buy it much, much cheaper as the acid, without the trade name - https://www.chemicals.co.uk/phosphoric-acid.

On rusty steel, you just paint it on, it reacts with the rust, kills it, and converts it. The metal then needs to be protected. I have used it many times, it is a clear liquid, similar to water.

 

[Activ]

I use food grade citric acid. Amazon will have it. Used it for years on car and van parts, tools, taps, tent pegs, cast turbo casings anything with a surface rust. Not tried it on rad internals tbh. 50g scoop per 5l bucket (general ratio), but experiment on one unit first. Wire brushing the surfaces speeds up the clean, time to soak, also hot water speeds up the process, boiling water more so, don't breathe in the steam though it really attacks the nostril linings! Like wise open cuts!! Wash it through / off thoroughly afterwards with clean cold tap water , being food grade mine goes down the drain after I've cycled everything I can through it.

With what's left of the citric powder, add castor sugar and make sherbert dib-dabs for the family, or diy haribo tangfastics. Practice with ratios to suit taste.

 

[ChrisJP]

I'm planning to take off all my old radiators, which I think have been running for ages without any inhibitor, hose them through in the backyard and restart the system as clean as possible and with loads of Fernox. If i buy new rads they most likely won't fit and i'll end up adapting all the pipework while spending money.

So my question is, is there a product i can use to treat the inside of the rads while i do this? I'm thinking down the lines of Kurust, which i've used on my camper, but swilling that through everything would cost a fortune. Just wondering if anyone has any bright ideas?

Thank you all, Dave

I can appreciate your reluctance to get new radiators. However, if a lot of black sludge comes out when you hose through a radiator, this is an indication of quite extensive corrosion within, and the likelyhood of pinhole leaks developing when in use again. I don't think there is any effective way of killing rust inside a radiator. All the phosphoric acid, vinegar etc treatments require the metal surface to be protected with paint after the treatment, which you obviously can't do inside a radiator.
Might be worth biting the bullet and installing new rads - could save a lot of hassle in the future!

 

[Harry Bloomfield]

All the phosphoric acid, vinegar etc treatments require the metal surface to be protected with paint after the treatment, which you obviously can't do inside a radiator.

From new, the inside of radiators is just bare steel, no coating at all. The addition of inhibitor, is meant to prevent the bare steel rusting.