If your boiler is more than 10 years old plan to replace it. Modern gas boilers are significantly more energy efficient.
Fitting spray taps will reduce the amount of hot water you use.
Improving your insulation is one of the best investments you could make in your home to reduce costs and improve warmth and comfort.
Older boilers operate at lower efficiency levels; typically 60%-70% so replacing your boiler means you will be saving money and heat.