Replacing Old Air Conditioning

Most split air conditioning systems give 10 to 15 years of service, and well-maintained systems often last longer. Eventually, though, repairs become more frequent, parts get harder to find, and the system costs more to run than a new one would. This guide explains when replacement makes sense and what is involved.

Signs It May Be Time to Replace

• The system uses R22 refrigerant. R22 has not been allowed for servicing since 2015, so a leak or a compressor fault on an R22 system usually means replacement.

• Repeated refrigerant leaks or a failed compressor on an older system.

• Rising running costs, or a room that no longer reaches the temperature you set.

• Noise, smells or water leaks that keep coming back after servicing. See air conditioner leaking water.

• Parts are no longer available for your model.

• The system only cools and you would like efficient heating as well.

What About R410A?

Many systems installed in the past 20 years use R410A. Existing R410A systems can still be serviced and repaired, so there is no need to replace a healthy system. However, since 1 January 2025, new single-split systems that use high-GWP refrigerants such as R410A have been banned from the market in Great Britain. Most new systems now use R32, which has a much lower global warming potential.

Repair or Replace?

If the system is under about ten years old, uses R32 or R410A and has a single fault, repair is often the sensible choice. If it is older, uses R22 or needs a major repair such as a new compressor, replacement is usually better value. Our F-Gas certified engineers will give you an honest view after inspecting the system. See top signs your AC system needs repair.

What Replacement Involves

1. Survey. We look at the existing system, the room, the pipework and the electrical supply, and check whether the current unit was the right size in the first place.

2. Safe removal. The old refrigerant is recovered by our F-Gas certified engineers, as the law requires, and the old units are removed for proper disposal.

3. Pipework. Existing pipework can sometimes be reused if it is the right size, in good condition and properly cleaned. Often, new pipework is the better option, and we check this at the survey.

4. New system. A new unit sized for the room is installed, tested and set up, and we show you how to use the controls.

A new system can often go in the same position as the old one, using the same wall openings and pipe routes, which keeps the work tidy.

What You Gain From a New System

• Lower running costs. Modern inverter systems adjust their output continuously rather than switching on and off, and many current models carry A++ or A+++ energy ratings.

• Efficient heating. A modern system can be one of the most efficient ways to heat a room. Read about air conditioning as a form of heating.

• Quieter operation. The quietest wall units are rated at 19 dB(A) on their lowest fan setting. See our guide to the quietest air conditioners.

• Better controls, with Wi-Fi and app control available on many models.

• Lower-impact refrigerant. R32 has a much lower global warming potential than R410A or R22.

What Does Replacement Cost?

Replacement costs are similar to a new installation. As a guide, one room typically starts from around £2,500, and multi-room systems usually range from £5,000 to £10,000+. We give you a clear written quote after a free survey. See our guide to air conditioning costs.

Frequently Asked Questions

Can you replace a system another company installed?

Yes. We can survey and replace systems fitted by any installer, and our engineers service all major brands.

Can I keep the old outdoor unit and change the indoor unit?

Usually not. Indoor and outdoor units are designed to work as a matched pair. An old outdoor unit will not normally work with a new indoor unit from a different range or with a different refrigerant.

How long does a replacement take?

Most single-room systems are fitted in a day. Multi-room systems take longer, and we confirm the timing in your quote.

Should I service my old system instead?

If it is in good condition, yes. A service can restore lost performance and catch small problems early. See our air conditioning servicing page.

Call 01772 288651 or use the form below to book a free survey. We will measure the room, recommend the right system and give you a clear written quote.

Last updated: November 2026.