How to fit your new Radiator Caps
For our latest fitting instructions please visit our new website and guide to fitting radiator caps.
RADCAPS Universal caps fits 99% of standard Lockshield and Wheelhead valves to a spindle size of 8mm x 5mm and a valve size of 25mm. The RADCAPS universal radiator cap fits both valves types.
To determine which is which on your radiator turn off your central heating so the radiators go cold, now switch the heating back on, whichever pipe leading to the radiator valves gets hot first is the WHEELHEAD valve.
The WHEELHEAD valve requires the RADCAP to be firmly pushed over the spindle and using the provided screw and allen key, tighten firmly. This allows the valve to be operated by turning on/off. The LOCKSHEILD valve requires the RADCAP to be firmly pushed over the spindle. This is for regulating the amount of water that passes through a radiator. They are not required for manual control and should be left in the pre-set position.
Please see diagram below showing you how to measure your valve. There are two types of valve on a standard central heating radiator LOCKSHIELD AND WHEELHEAD, RADCAPS fits both!