HVAC Room Ventilation

[gimlet17]

Was curious if anyone has come across this. In the furnace room of a townhouse in South Jersey with no basement, there is a high and a low 7" duct that openly vents the furnace room to the attic above. The furnace and boiler exhausts are appropriately vented separately. Have never seen this set up and I was wondering if it is safe to take it down or not. Only thing it seems to be doing is letting heat in in the summer and cold in in the winter. Thanks.

[HeyBob]

You need to leave it there. Combustion air source.

[eastaire]

On older heater with natural draft flues. The lower vent would have been installed at burner level to supply oxygen to the flame and the upper would be to aid the natural draft of the flue. New heaters with induced darft only need one properly sized to the heater. You can not take oxygen from the house so it is piped in from the attic or somewhere else. In the summer when the heater is not in use, you can install man. damper and close them off but do not forget to open them when heater is in use.