From this photo, it looks like a concealed fan-coil / through-wall HVAC unit, not a conventional furnace. It is very likely intended to provide both heating and air conditioning, but I cannot confirm the exact configuration without seeing the model label or the outside side of the wall.

The visible cylindrical blower at the bottom is the indoor fan. Once the wall is finished, the cabinet would normally be covered by a grille or finished enclosure.

How it probably works

The unit pulls room air through a return opening, passes it over a heating/cooling coil, and blows the conditioned air back into the room.

There are a few common versions of this type of system:

• Heat-pump unit: provides both AC and heat by reversing the refrigeration cycle. It gets heat from the outside air in winter and rejects heat outside in summer.
• AC + hydronic heat: cooling comes from refrigerant or chilled water, while heating comes from hot water supplied by a boiler.
• AC + electric heat: refrigerant provides cooling and an electric heating element provides heat.
• Less commonly, it could be a fan coil connected to a central building chilled-water/hot-water system.

From the picture, I do not see anything resembling a gas burner, flue, or furnace heat exchanger, so I would not expect this particular cabinet to be a conventional gas furnace.

Where does the hot/cold come from?

The blower itself doesn’t create heating or cooling. It only moves air.

If this is a heat pump, there will normally be either an outdoor condenser/heat-pump connection through the exterior wall or refrigeration piping going elsewhere.

If it is a building fan-coil system, pipes would bring hot water and chilled water to the unit.

There appears to be some piping/tubing going into the right side, which makes a fan-coil arrangement quite plausible.

Is it noisy?

Potentially somewhat noisier than a traditional central HVAC system, because the blower is physically located inside the room or immediately behind the wall instead of being in a basement/utility room.

However, a good modern unit should not be objectionably loud. You would normally hear:

• airflow,
• a low blower/fan sound,
• possibly compressor sound if the compressor is actually incorporated in this unit.

If the compressor is outdoors or elsewhere in the building, it should be considerably quieter.

The large squirrel-cage blower visible in your photo is generally capable of running fairly quietly at low/medium speed, but at high speed you will definitely hear airflow.

One important clue: this does not look like a typical hotel PTAC, where the entire AC/heat-pump assembly slides through an exterior wall underneath a window. This looks more like a built-in residential/commercial fan-coil HVAC system.

To identify precisely a closer picture of the unit, particularly any manufacturer/model-number sticker, and ideally a picture of the opposite/outside side of that wall is needed, I can tell you much more specifically:
exactly what type it is, whether it has AC, what produces the heat, whether there should be an outdoor condenser, and approximately how noisy that particular type is.