Its time to change the old combi oil boiler, so the preliminary research has just begun. (for 2 bed cottage, 1 shower only at a time, only 2 adults in residence generally)
My other half asserts that a multipoint water heater is more energy efficient because the heat exchange is direct ie flame to pipe/plate, as opposed to a combi where heat for dhw is indirect. I can't find any published ratings (like sedbuk) for water heaters to verify this.
Any help with the following questions would be very much appreciated.
1, Is this the case? & is the efficiency difference significant?
2, Do some combies exist that also have a direct heat exchanger for the dhw and if so which ones?
Many thanks[/b]
My other half asserts that a multipoint water heater is more energy efficient because the heat exchange is direct ie flame to pipe/plate, as opposed to a combi where heat for dhw is indirect. I can't find any published ratings (like sedbuk) for water heaters to verify this.
Any help with the following questions would be very much appreciated.
1, Is this the case? & is the efficiency difference significant?
2, Do some combies exist that also have a direct heat exchanger for the dhw and if so which ones?
Many thanks[/b]