FITTINGS FOR ALL CAST IRON RADIATORS

Please read ALL the listing description to make sure you have the CORRECT SIZE

Reducing Bushes - End Plugs - Bleed Valves

BSP NAME                              ACTUAL  DIAMETER               FITS HOLE  APPOX

    1/2"                                              20.995mm                                    3/4"

    3/4"                                              26.441mm                                     1"

    1"                                                 33.249mm                                  1 1/4"

    1 1/4"                                           41.91mm                                    1 1/2"

    1 1/2"                                           47.803mm                                  1 7/8"

    2"                                                 59.614mm                                  2 1/4"

HELPFUL INFORMATION:

This is the point at which to think about connecting the radiator to a modern central heating system. It is unlikely that all bushes and plugs will fit a modern central heating system so you may need to replace some. All cast iron radiators will have two reducing bushes, also known as valve bushes. These are the point of entry and exit for the water and are usually located at the bottom of the radiator. It is the reducing bushes that are most likely to need replacing to fit a modern central heating system.

At the top of the radiator there will be one blanking plug and one bleed bush. These are less likely to need replacing unless they are broken or in the wrong position. To remove, unscrew the bush or plug using a spanner. All reclaimed cast iron radiators that we have come across have right-hand thread bushes and plugs, so unscrew to the left. The insides of reclaimed cast iron radiators are usually pretty rusty so they require a good amount of torque to unscrew the bushes. We tend to use a short piece of scaffold pole to extend the length of the spanner handle and provide more torque on the bush.

Most modern thermostatic or manual radiator valves have a 1/2″ BSPT (British Standard Pipe Tapered) connection to the radiator, which equates to a 21mm hole into which the valve tail is inserted. 

A little aside about BSP sizes: British Standard Pipe fittings come in parallel or tapered thread. The fittings on reclaimed cast iron radiators are usually BSPT (ie tapered). The seal is made at the contact between the male and female threads with their tapered shape meaning that the contact area between the threads increases with each turn. To ensure a strong seal is acheived, it is absolutely essential that a good sealant is used when screwing in the end bushes. This is because cast iron, especially reclaimed cast iron, is often pitted. For this purpose, we recommend LSX Sealant.