Office air conditioning

Why offices overheat

Most offices get hot for the same few reasons. People give off heat, and so do computers, screens, printers and lighting. Add a wall of south or west-facing glass and a meeting room with the door shut, and a floor that felt fine at nine can be stuffy by two. Many older buildings were never designed for the number of people and devices they now hold, and opening windows lets in traffic noise and fumes as well as warm air.

The Health and Safety Executive says there is no legal maximum working temperature, but employers must keep the temperature at a comfortable level and provide clean, fresh air. Air conditioning is one of the most reliable ways to do that through a hot spell, and most modern systems are heat pumps, so the same units heat the office in winter too.

Choosing the right system for the space

We start with a site survey. We look at the size and use of each room, the glazing, the number of people and the equipment, and where the outdoor units and pipe runs can go. Then we recommend the simplest system that will do the job well.

• Single offices and small suites: a wall-mounted split is quick to fit and easy to control. A single room split is £1,200 to £2,200 + VAT, including supply, installation, commissioning and F-Gas paperwork.
• Several rooms: a multi-split runs two or more indoor units from one outdoor unit, so each room has its own control.
• Open-plan floors with a suspended ceiling: ceiling cassettes spread air evenly from above and sit flush with the ceiling grid.
• Offices where you want nothing on show: ducted units hide above the ceiling with only grilles visible.
• Whole floors or buildings: VRF serves many zones from shared outdoor plant, and some systems can heat one zone while cooling another.

Larger and multi-room systems are priced after survey, and you get a fixed-price quote before any work is booked.

Fresh air is a separate job

A split air conditioning unit cools and heats the air already in the room. It does not bring in fresh air. If a room feels stale or drowsy even when the temperature is right, the problem may be ventilation rather than cooling. We look at both on the survey, and where a space needs more fresh air we can talk you through ventilation and heat recovery options alongside the air conditioning.

Installed out of hours

Office work is easier when the office is empty. We can fit indoor units, run pipework and make the noisy holes in the evening, overnight or at the weekend, and leave each area clean and usable for the morning. On a multi-floor job we can work floor by floor, so only one area is affected at a time. We agree access, keys, alarms and parking with you or your building manager before we start.

If you lease the office, check your lease before you commit. Landlords usually want to approve outdoor units, wall openings and roof work, and some buildings have rules about where plant can go. We can provide drawings and product details for the landlord’s approval. Our article on leasehold consent for air conditioning explains what to ask.

F-Gas leak checks and records

Most office systems contain fluorinated refrigerant, and the business that operates the system has legal duties for it. GOV.UK says leak check intervals depend on the size of the charge in tonnes of CO2 equivalent (kg of refrigerant multiplied by its GWP, divided by 1,000):

A small R32 split may sit below the 5 tCO2e line, but a larger multi-split or VRF system often does not. We work out the figure for each system, carry out the checks, and keep the records you need. Any company that works on these systems must be F-Gas certified, and we are.

TM44 inspections for larger systems

If the air conditioning in your building has an effective rated output of more than 12 kW, GOV.UK’s guide to air conditioning inspections says it must be inspected by an accredited energy assessor, with inspections no more than five years apart. Separate units controlled by the same person in one building count together, so a few splits in an office can cross the line. We are not energy assessors, but we can help you arrange and prepare for a TM44 inspection and put right anything the report finds.

Keeping it running

Office systems work hard through the summer, and a blocked filter or a dirty coil soon shows up as weak cooling or a musty smell. An office maintenance contract puts servicing, F-Gas leak checks and records on a fixed schedule, priced with your quote. If something does go wrong, our 24/7 line takes the call and we reply to enquiries the same working day. We cover offices across London and the South East, from single rooms to whole buildings.