Shut the door! Why keeping doors closed is vital for your air conditioning’s efficiency

It might seem like a small thing, but keeping doors closed while your split air conditioning system is running – whether it's heating your Ripley premises on a cool spring day like today, or cooling it during warmer weather – is one of the simplest yet most effective ways to ensure its efficiency. Leaving doors open, even just a crack, can significantly undermine your system’s performance, leading to wasted energy, higher costs, and reduced comfort. This guide explains why this simple habit is so important.

Why open doors sabotage your air conditioning

Your air conditioning system works hard, using energy to carefully bring the air inside a specific room or area to the temperature you’ve set on the thermostat (the 'setpoint'). It creates a pocket of 'conditioned' air.

An open door acts as a large gap, allowing:

1. Conditioned air to escape: the heated or cooled air your system just produced flows out.
2. Unconditioned air to enter: outside air (which might be colder, hotter, or more humid) or air from unconditioned spaces (like corridors, warehouses, or lobbies) flows in.

This constant, uncontrolled exchange of air forces your air conditioning system into a continuous battle against the outside environment or adjacent spaces.

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The consequences of leaving doors open

Allowing this air exchange has several negative impacts on your business:

1. Massively wasted energy and higher costs: this is the biggest consequence. Your AC unit has to run much harder and for much longer to try and counteract the escaping conditioned air and the incoming unconditioned air. It’s like trying to heat your building in winter with the main entrance wide open – a huge amount of energy is simply wasted straight outside or into areas you aren’t trying to condition. This directly translates to significantly higher electricity bills.
2. Reduced comfort and effectiveness: because the system is constantly fighting a losing battle, it may struggle to reach or maintain the desired temperature. This can lead to uncomfortable conditions for staff and customers – draughts, uneven temperatures, or the space never feeling quite warm or cool enough.
3. Increased wear and tear on equipment: making your AC system run flat-out for extended periods puts unnecessary strain on its components, especially the compressor and fans. This can lead to more frequent breakdowns and shorten the overall lifespan of your expensive equipment.
4. Poor humidity control (when cooling): during warmer periods when the system is cooling, open doors allow humid outdoor air to flood in. This makes the space feel sticky and uncomfortable, even if the temperature is relatively low, as the system cannot effectively dehumidify the constantly changing air.
5. Introduction of dust and pollutants: open doors provide an easy pathway for dust, pollen, vehicle fumes (if near an external door), and other outdoor pollutants to enter your conditioned workspace, potentially affecting indoor air quality.

It applies equally to heating and cooling

Remember, this principle is exactly the same whether your system is providing heating during cooler periods or cooling during warmer weather. In either case, you are paying to condition the air within a specific space, and open doors let that investment leak away while inviting in air you then have to pay to treat.

Simple actions for significant savings and comfort

• Keep external doors closed: ensure main entrance/exit doors are kept shut as much as possible when the air conditioning is running.
• Close internal doors: shut doors connecting conditioned rooms to unconditioned spaces (e.g. hallways without AC, stock rooms, kitchens, warehouses).
• Use door closers: consider installing automatic door closers on high-traffic doors to ensure they don’t get left open accidentally.
• Educate your team: explain to staff why keeping doors closed is important for energy saving and comfort. A simple reminder can make a big difference.
• Consider signage: a polite sign (“Please keep door closed – air conditioning in use”) can be helpful, especially for customer-facing doors.
• Don’t forget windows: the exact same logic applies to windows – they should also remain closed when the heating or cooling is active.

Our conclusion

Keeping doors closed while your split air conditioning system is operating is a fundamental aspect of using it efficiently. It’s a simple, no-cost habit that directly reduces energy waste, lowers your electricity bills, improves comfort levels for everyone in your Ripley business, and helps prolong the life of your equipment. Make it a standard practice – shut the door, save energy, stay comfortable!

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Call us on 01773 301 300