air bricks needed or not?

[davsas]

hi all, i have a warm air heating system in my 3 bed house. It has a flue that goes up through the house and out through the roof. Question is, vent in the kitchen where the boiler is. Im told they have to be there to get rid of fumes(i thought that was what the flue was for!) but there are 2 air bricks in the kitchen, and the cold air they let in is canceling out the heat, so the kitchen is frezzing even with heating on full, and the cold draught goes in to the living room as well. Do i need both of there open? Thanks in advance, dave

 

[namsag]

They are not to let the fumes out , Its to let air in for proper combustion of the appliance .
Whether you need 2 is another question
If correctly sized ,one would do and anti draught ones are avialable