difference in one furnace heating and zoned heating (installed, rooms, radiators)

[neeshera]

We recently saw a house on the market for sale. It did not have zoned heating and had only one furnace. We were told that what we should do is close the vents in the rooms that did not need heating. So this would then basically function like zoned heating.

I am not very knowledgeable about this matter. Yet I feel this information is most likely wrong.

Can someone throw more light on this, please?

[Cosmic]

I assume this is forced hot air.

In general it sort of can work, probably depends on the particular house. Lot of forced hot air systems don't work all that well, no matter the number of zones. Uneven temps in different places, return air does not exactly work as advertised.

Lot might depend on the particular system. Age, condition, quality of construction, how well the duct work is designed / installed, what type of dampers / registers, etc and how well they work.

Shutting off rooms in forced hot air can get the rest of the system unbalanced and you have to monkey with it to attempt to get it into a satisfactory condition. Works a lot better with forced hot water systems where you can shut off radiators.

I might have them run the system, even if it is in the summer and see what I could discover. See how things seem to function. The devil is probably in the details with any one particular system.

[Padgett2]

The thermostat controls and air intake are usually placed so that the air flow is best to keep an even temperature all over. If you shut off some of the rooms or vents, you will change this. And it probably won't be for the best. It might work OK for you, but it might not.

[K'ledgeBldr]

Non-zoned system: Furnance supplies air to individual rooms. Some systems have one return, others may have several smaller returns. There's one t/stat that controls the whole system.

Zoned system: Same as above but, each individual room has it's own t/stat that controls a damper and the furnance function.
(for example; one room has t/stat set for 68 and another is set for 72. Each t/stat will control the damper for that room until the desired temp is achieved. Once it is achieved it will close. While the other room still has the demand. Once all rooms have meet their demand the furnance will stop.