What is a FLUE Gas Heat Recovery System (FGHRS)?

FGHRS recover heat from waste flue gases to preheat the cold water entering the boiler, lowering the amount of energy needed to warm the water up to the required level. Almost all modern boilers already have some sort of heat recovery built in, making condensing boilers much more efficient than older ones. Even so, FGHRS can further increase the efficiency of these condensing boilers in most cases, delivering the same amount of heat with up to 4% less gas.

The Ideal Logic Code Combi ESP1 has a built in FGHRS.