Why is there a vent on the ductwork coming right from the furnace? I have a typical furnace for a 1400sqft house in Michigan. I also have central air which runs through the same duct work. There is a separate room in the basement for the furnace, hot water tank and workshop area. No one ever spends much time in that room if any. Should I leave the vent open for both heat and air conditioning or should it be open for one/closed for the other? Please let me know. Thank you
Furnace installers and/or home owners will put a register in the duct work to provide some heat in the winter to that area. The number of these supply registers is determined by the typical use and desired temperature of this area. I recommend that all basements should have at least 2 supply registers and 1 return register in the basement/equipment area just to keep that area slightly warm and the air fresh. If you are going to finish that area to be used as living space, then more supply and returns will be needed. Also you may want to close the supply registers in the summer when using the A/C since cold air is heavy and will move to the lowest level in the house. Keeping the register you originally inquired about either open or closed would be your choice.
D George-unless you’re talking about an all electric building NEVER place a return air grill/vent in an equipment room. I say never because most people (even contractors) fall woefully short of understanding barometric pressure issues. Frequently a return in the equipment room of fossil fuel appliances is enough to overcome the natural or assisted draft of a fossil fuel system. This can easily result in the byproducts of combustion, including deadly carbon monoxide being drawn back into the occupied space with catastrophic results. GAMA and National Fuel Gas codes have very strict and sometimes complex rules for doing so. Since we don’t know the competency of the homeowner or technicians we must rely on municipal inspectors to verify the safety of it. Unfortunately, many of them also lack understanding of these codes and their application. Better off just not doing it-unless there is verification the system will work under all circumstances.