Radiators have two valves, one at each end. These are to:
- Allow for the removal and drainage of the radiator without turning off the whole system
- To restrict water flow in the radiator and send it to radiators further away.
The valve, known as a lockshield valve, can be adjusted to balance the radiator. When a system is balanced perfectly, all radiators will heat equally without some warming quicker at the expense of others.
It sounds simple, but it’s certainly not. When a heating engineer balances the radiators, it’s only a quick intuitive estimate – but this is usually adequate. The engineer will close the valves and then half open the ones closer to the boiler. Then those further away will be opened slightly more.
To counteract the natural movement of heat rising, radiators upstairs have their valves closed more than those downstairs. Because of the complexity, you could be fiddling about for hours trying to get the perfect combination. However, if it’s slightly off it doesn’t really matter, as long as the radiators do heat up in good time.