Quick answer
A compressor air conditioner needs a way to remove heat from the room. “Without an exhaust hose” can mean an evaporative cooler, a split with refrigerant connections or a wall unit with outdoor openings. These devices are not equivalent.
Three common sources of confusion
A fan simply moves air. An evaporative cooler can reduce air temperature in suitably dry conditions while raising humidity. Its effect depends particularly on temperature, humidity and ventilation. A fixed promise of a one- or two-degree reduction would be unreliable.
| Device | Heat path | What to check |
|---|---|---|
| Evaporative cooler | Water evaporates into room air | Raises humidity; does not replace a split system. |
| Split system | Connections to outdoor unit | No large air hose, but still an outdoor connection. |
| Wall monobloc | Air exchange through wall openings | No separate outdoor unit, but alterations to the façade. |
Why heat must leave the room
A compressor moves heat from the cold side to the warm side of the device. If both release energy into the same closed room, electrical input adds further heat. An open refrigerator therefore cannot serve as room air conditioning.
Stored ice can absorb heat temporarily. Refreezing it produces waste heat elsewhere. This also does not replace a lasting route for heat to leave the building.
Questions to ask before buying
The number and diameter of holes for a wall unit depend on its design. Clarify consent and permits before ordering. Avoid persistently high humidity and damp surfaces: extra evaporation can worsen comfort in an already humid room.
- Is this a compressor appliance or simply a device with a water tank?
- Where is the extracted heat released?
- What wall openings, connections or brackets are required?
- Can you monitor humidity and clean the water tank hygienically?
Frequently asked questions
Can I continuously cool a closed bedroom without an outdoor connection?
Not with an ordinary compressor air conditioner that releases all its waste heat into the same room. A lasting solution requires heat to leave the room.
Does “no outdoor unit” mean “no building work”?
No. A fixed wall unit can avoid a separate outdoor unit while still requiring wall openings and possibly condensate drainage.
Find a suitable installer
Search companies by canton and compare services and coverage. Send the same project description to several installers for comparable quotes.
Find companies by cantonSources and scope
For private households in Switzerland. Manufacturer information applies to the named models. Local requirements and system suitability need individual assessment. Sources link to their original language.
- EnergieSchweiz: Raumklimageräte ↗Checked: 2026-10-02
- Energie und Umwelt der Westschweizer Kantone: Climatiseur mobile ↗Checked: 2026-10-02