Cast Iron Radiator Restoration

At Heritage we understand that a thorough and effective restoration process will insure maximum performance, efficiency and a floorless finish.

In the past we had used the restoration process known as shot blasting, however we found this process to be abrasive to the exterior castings even to the extent of irreversible damage. Additionally the shot blasting process will not clean the interior of the radiator which is in fact worse than the outside. These radiators have been on working systems for the best part of 70years and therefore at times can accumulate a build-up of debris and sludge. Blasting the outside of the radiator and simply flushing them through really doesn’t make an impact at removing this. We believe the restoration process that we have now adopted insures a thorough internal and external cleanse and will bring these radiators back to the efficiency of when they were manufactured.

Removing of old fittings

The first stage of the restoration process is to carefully remove all the old radiator fittings. These will be replaced with new reducing bushes, enabling the radiators to be compatible with modern heating systems.

Cleaning and stripping

The radiator is now immersed in a tank that is filled with a caustic solution, which the water board also use to clean the drains with. When heated this solution will strip the paint from the outside of the radiator and attack the built-up sludge on the inside. The radiators are left in the tank for between 2-4 days depending on their condition. Once we are happy the radiator has been thoroughly cleaned inside and stripped on the outside the radiator is removed ready to be washed off using a high pressure jet-washer with specially made attachments which fit inside the radiator to really make sure it is cleaned back to its original condition.

Fitting new bushes

All new reducing bushes are now fitted to suit new Thermostatic Radiator Valves. Please note that Heritage Cast Iron Radiators will fit 15mm bushes for bottom feed and returned on every radiator including the customer’s restorations. If a different configuration or bush size is required, we would request the customer to specify this at the time of order.

Pressure testing

It is of paramount importance that the radiators are tested correctly. Some companies will test the radiators with air, however we feel the best way is to test with water. We fill the radiator up with water to mimic how it will be on a working system. We use a water supply which has been tested to run at 6 bar a pressure. A normal heating system will work at between 1.2 and 2 bar so we have a safety margin of over 4 bar of pressure. Testing the radiators using this method whilst stripped down to its bare cast, makes it very easy to see if there is a leak. If a leak is detected, then the radiator will go back to the workshop where our radiator technicians will carry out the repair. We have thousands of radiators in stock so spare sections are easily available. Once we’re happy the radiator has been tested and no leaks detected the radiator is signed off and is now ready for painting.

Radiator spraying

We have two purpose built Spray booths in which we use a wet spray system to finish the radiators.  Two coats of primer are applied before the finishing colour can go on.  Radiators can be finished in any colour, please see our Paint Finishes to see our stock colours. Alternatively we work with all the main colour experts for inspirations like Farrow & Ball, Little Green Paint Co, Laura Ashley and Paint and Paper Library to name but a few. We can also colour match any colour on request.  All we ask for is a sample to be supplied. There is no extra cost charged for any of these colours. If it’s more of a metallic colour you are after then please look at the Ardenbrite colours for inspiration. These are the only paint finishes we charge extra for which is £60 per radiator. 


You can have your radiators in a hand polished finish. This is a truly impressive and wondrous to really make a statement from the radiators. It is carried out off site by specialists to achieve the best finish. Polishing carries a charge of £19.50 per section as you can imagine it is very labour intensive. Polished radiators do however require a little maintenance from time to time by applying some WD40 on them to keep any moisture away from the bare polished cast.

If you have any further questions please do not hesitate to contact us.