It surprises some people to know that boilers are not generally considered domestic rubbish and may not be collected by the local authority if left at the kerbside with your standard household waste. Here are some options available:

The company or engineer who installs your new boiler – you can ask them to take your old boiler away. They won’t give you anything for it, but it is a hassle-free solution.
Local recycling centre – some centres have provision to dispose of metals and can recycle boiler components. Always check with your local authority first.
Local council ‘bulky waste collection’ service – do check first as every council has different rules but some will collect boilers from the boundary of your property for a set fee (ranging from £20-£40).
Scrap yards – the Government no longer offers a scrappage scheme, but your local scrap yard is worth contacting. As the metal can be recycled you could receive a small payment for an old boiler. Copper pipes also have value so, depending on the price of copper at the time, you could earn up to £70.