Office Air Conditioning
The complaint in most offices is not that the air conditioning is broken. It is that half the floor is too cold and the other half is too warm, and someone has taped over the controls. That is a design and zoning problem, and it is fixable.
Why one office is never one temperature
Heat does not arrive evenly. A south-facing desk beside glass gains heat all afternoon while the internal side of the same floor gains almost none. A meeting room with ten people in it produces a burst of heat for an hour and then nothing. A comms cupboard produces heat all night.
If those areas share one thermostat, somebody is always uncomfortable. The fix is to design the zones around how the heat actually behaves, and to put the controls where they reflect the space rather than where the cable happened to reach.
The things that decide the design
- Occupancy. People are a heat source, and a desk density of one per six square metres is a different building from one per twelve.
- Glazing and orientation. Which elevations get the sun, and when.
- Equipment. Screens, servers and kitchen appliances all end up as heat in the room.
- Hours. A trading floor running from six in the morning is not a nine-to-five office.
- The ceiling. Whether there is a void, and how deep, decides whether cassettes and ducted units are possible or whether wall units are the only realistic option.
Noise, which nobody asks about until afterwards
An office is a quiet space and people work in it all day. Indoor unit noise matters more here than almost anywhere else, and it is set by the equipment chosen and where it is positioned relative to desks. It is worth raising at survey. Outdoor unit noise matters too, particularly if there are neighbours or residential windows nearby.
Controls people will actually use
The best system in the world fails if the people in the room cannot work it. We set the controls up so that the sensible thing is the easy thing, lock out the settings that cause heating and cooling to fight each other, and show whoever manages the office how to run it. Where there is a building management system, we make sure the new plant talks to it properly rather than running independently.
What it costs to run, and how to reduce it
Running cost is driven by how well the system is matched to the space, how it is controlled, and whether it is maintained. An oversized system short-cycles and wastes energy. A dirty filter makes the unit work harder for the same cooling. Controls left fighting each other can double consumption without anyone noticing, because the building still feels roughly right.