Combi boilers are far more efficient than older boilers because they use more gas due to their design and the deficiencies after long time usage. Older boilers over 10 years old are almost certain to have less efficiency than the new combi boilers available today. T&S offer only ‘A’ rated energy efficient combi boilers which equates to around 90% or more in saving fuel, that means a lesser impact on your wallet.
This means that the energy extraction of heat from the gases normally wasted in older boilers isn’t wasted in combi boilers. This loss of energy is down to the gases that are being ejected out of the flue in non-combination boilers. Combi boilers have a secondary heat exchanger so even if there are gases escaping from the primary heat exchanger it is still caught in the secondary heat exchanger. This means there are fewer gases that escape and at a lower temperature which means more heat is kept. The effect of this cooling method causes water vapour to condense (hence the name combi or combination boiler) which will form water droplets that are drained out of the boiler into a drain.