The honest differences between split and window units — running cost, noise, what installation really involves, what happens in a power cut, and which one makes sense if you are living in a rented house.
This question comes up in almost every enquiry we get between February and May. People have usually already been told by a shop that a split is "better". It is a more complicated answer than that, and the right choice depends far more on your house and your electricity supply than on the machine.
Here is how we would think about it for a home in Sasaram, Dehri-on-Sone or any of the surrounding towns.
The short version of the difference
A window AC is one box. Compressor, coils and fan all sit in a single unit that goes into a window opening or a hole cut in the wall. A split AC is two boxes joined by copper pipes — a slim indoor unit on the wall inside and the noisy compressor outside.
That single difference drives almost everything else.
Side by side
| Point | Window AC | Split AC |
|---|---|---|
| Installation | Sits in a window or a wall opening. Quick, few parts, easy to remove. | Needs core drilling, copper piping, drain routing, wall mounting and a vacuum pull. Takes hours. |
| Noise inside the room | Compressor is in the room. Noticeably louder. | Compressor is outside. Indoor unit is quiet. |
| Cooling for the same tonnage | Comparable, provided it is sized correctly. | Comparable, spreads air more evenly in a wide room. |
| Servicing | Simpler. The whole unit comes out and can be washed properly. | More involved. Indoor and outdoor cleaned separately. |
| Shifting to a new house | Straightforward. Lift out, refit. | Needs gas recovery, fresh pipe work and reinstallation. |
| Space and looks | Blocks a window. Bulky. | No window lost. Neater inside. |
| Outdoor space needed | None. | A wall or terrace spot with free airflow. |
Running cost
This is where people expect a bigger gap than exists. What decides your monthly bill is the star rating and whether the compressor is inverter type, not the shape of the box. A high-rated inverter split will use less than an old window unit — but a high-rated window unit and a basic non-inverter split are much closer than most shops suggest.
Two things move the bill more than the split-versus-window decision ever will:
- Correct tonnage. An undersized AC runs continuously and never satisfies. An oversized one cools quickly, cuts out, and leaves the room damp.
- The room itself. A west-facing room with a thin roof and a gap under the door will drink electricity regardless of which machine you fit. Curtains and sealing that gap are cheaper than a bigger AC.
Power cuts and voltage — the part that matters here
Summer evening supply in much of Rohtas and Kaimur sags and cuts out. Both types of AC suffer from it in the same way: the compressor tries to restart against pressure, draws heavy current at low voltage, and takes damage over time.
The protection is the same for both — a correctly rated stabiliser, proper earthing, and a dedicated point with cable thick enough for the load. Many inverter units claim a wide voltage range, but in a mohalla where voltage collapses on a hot evening we still recommend a stabiliser.
Do not skip this: never run either type of AC off an extension board or a shared socket, and never leave it without earthing. Low voltage plus a loose connection is how terminal blocks burn and compressors fail — and that failure is not covered by anything you can do afterwards.
Rented house or your own?
This is often the deciding factor, and it is the one people think about last.
If you are renting, a window unit is usually the sensible choice. It needs no core drilling through the landlord's wall, no permanent bracket outside, and when you move you lift it out and take it. Shifting a split AC means recovering the gas, cutting or re-running pipes, fresh drilling at the new house, and a full reinstallation — the cost adds up, and the pipe is often not reusable at a new length.
If it is your own house, a split makes more sense. It is quieter, it does not cost you a window in a room that may already be short of light, and over a decade the installation cost is spread thin.
One caution for split units: you need a genuine outdoor location. A unit shoved into a narrow shaft, boxed behind a grille or crammed under a staircase will run hot and cool poorly for its whole life. If there is no good outdoor spot, a window unit will serve you better than a badly placed split.
Room size and tonnage
Rough guidance for our climate, where April to June routinely crosses 40°C:
- Small bedroom, well shaded — 1 ton is usually enough.
- Standard bedroom — 1 to 1.5 ton depending on sun exposure.
- Large room, top floor, or west-facing — 1.5 ton and often more.
- Drawing room with a lot of glass or frequent door opening — 2 ton territory.
Adjust upwards for a top-floor room under a concrete roof, a room that takes afternoon sun, or a room where several people sit. Adjust down for a shaded ground-floor room with thick walls. If you are unsure, tell us the room size and which direction it faces when you call — it is a two-minute conversation and it saves a bad purchase.
What we would tell a neighbour
Own house, decent outdoor wall, want a quiet bedroom: split. Rented house, or no sensible place for an outdoor unit, or you expect to move within a few years: window. Either way, size it for the room, fit a stabiliser, and get the installation done properly — a good machine installed badly performs like a bad machine.
Charges for installation, servicing and repair for both types are on the rate list, with GST extra and parts billed at actual cost after we tell you. Call +91 96315 11974 or use the contact page and we will ring back within an hour.
We handle AC work in Sasaram, Dehri-on-Sone, Mohania, Bhabhua and Aurangabad — see the service areas page for the rest, and the blog for more on keeping a unit working through the summer.
Frequently asked questions
A window unit, in most cases. It needs no core drilling through the landlord wall and no permanent outdoor bracket, and when you move you lift it out and refit it. Shifting a split means recovering the gas, new pipe work and a full reinstallation at the new address, which often costs more than people expect.
Not because it is a split. The bill is decided by the star rating and whether the compressor is inverter type. A high-rated inverter split will beat an old window unit, but a high-rated window unit and a basic non-inverter split are close. Correct tonnage for the room matters more than either.
A room of that size usually sits at 1 to 1.5 ton. Go towards 1.5 ton if it is on the top floor under a concrete roof, faces west and takes afternoon sun, or has several people in it regularly. A shaded ground-floor room with thick walls can manage on 1 ton.
In most mohallas here, yes. Summer evening voltage drops sharply and a compressor repeatedly trying to start on low voltage takes damage that shows up as a failure later. Even where the unit claims a wide operating range, a correctly rated stabiliser plus proper earthing and a dedicated point is cheap protection.
Want a hand with this?
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