We have a gas furnace and there are about 15 floor vents throughout the house. We though that by closing some of the heating vents in rooms which we rarely use (spare bedroom for example) we would save money on the heating bill. However, we have been told by a furnace specialist that this is not true and that it will make no difference to the bills because the temperature is only measured from one place (the thermostat) and whether or not the heating goes to all the rooms is irrelevant. In fact, he said that by closing vents we could actually damage the furnace by causing overheating.Is this true? Is there any benefit to closing vents during the Winter? I would imagine that by closing vents we would at least ensure that more of our heating is directed to the rooms we spend the most time in.
I will completely agree with GG You will have more flow in other vents causing other rooms to heat quicker. The more you can shut down the better. But do not shut down rooms with water in them on very cold days or you could be out a very much larger bill due to freezing.
You are absolutely correct and your furnace specialist is mistaken. As long as you keep the vents nearest to the thermostat wide open, you will save money. As far as overheating and causing damage, I could run you through the relief calculations, but it is unnecessary. The upper limit on you stack switch is designed for that possibility. It will protect you from damaging your heat exchanger. My three bedroom house has the vents in two bedrooms that are closed and sealed with duct tape. The vent in two of the bathrooms are half closed and a vent in the kitchen is 3/4 closed. It has been this way since the kids moved out seven years ago. We have continually lowered the amount of energy we use in the house by being vigilant to wastefulness. My bride of 17 years and I take joy in reducing our energy use.
