Age, refrigerant type, repair history and the size of the bill decide whether to repair or replace air conditioning. A single fault on a young unit usually favours a repair, while repeat faults on an older one favour replacement. A single-split replacement typically costs £1,500 to £3,000 fitted, a useful figure to weigh against any repair estimate.
When a repair bill raises a bigger question
A unit stops cooling well. That forces a choice nobody wants to make: pay for a fix, or plan a new one. Age, gas type, repair history and the size of the bill all point toward an answer. If the unit has stopped outright, our checks before calling out an engineer is worth reading first.
However, none of them settles it alone. Since reading them together gives a clearer view, this guide takes each one in turn.
How age and history change the calculation
A young unit with one failed part is usually worth fixing outright. The rest of the hardware still has plenty of life left. A single fault on a sound machine rarely justifies a whole new system. The same logic applies to call-outs through our Exeter repair page: a young unit is usually worth fixing.
An older unit failing for a second or third time is a different case. Each fix then becomes a bet against a machine that may be worn elsewhere too.
A costly repair on an older unit deserves a second look. The useful test is simple: set the repair bill against the fitted price of a new system. Still, this is a starting point for a conversation, not a fixed rule for every home.
Why gas type matters
Refrigerant rules have tightened over the years. Great Britain is phasing down HFC refrigerants by 79% by 2030, measured against average use in 2009 to 2012. That means less of these gases reaches the market each year.
For larger systems, the rules go further. You cannot refill a system holding 40 tonnes or more of CO2 equivalent with new gas above a warming potential of 2,500. Reclaimed or recycled gas is allowed for such systems only until the end of 2029.
Most home split units sit well below that size, so the ban rarely applies to them directly. Still, it is worth asking which gas your unit uses. If a leak means a full top-up, that gas and its supply become part of the repair bill.
Who can work on the gas
Any repair that opens the refrigerant circuit needs a qualified engineer. GOV.UK guidance is clear that it is against the law to work with F gas without the correct qualifications. Therefore a cheap fix from someone without them is a false saving.
The qualification also comes in categories. For example, a Category 2 holder can install, service and recover gas from systems holding under 3kg. Meanwhile, a Category 4 holder can only carry out leak checks without breaking into the circuit. Anyone booking Gloucester air conditioning repair can ask to see the engineer’s category before work starts.
Efficiency and what it costs to run
A unit that still works can still cost more to run than it should. Energy labelling rules cover air conditioners, grading them by efficiency class from A+++ downward. That label gives you a fair way to set an old unit against a current one.
An old unit that keeps needing small fixes can also cost more to run day to day. That extra cost rarely shows up on the repair bill itself.
A running-cost gap does not usually justify a swap for a unit that is otherwise sound. Still, it is worth weighing once a unit is older and failing. At that point, a fix often sits against a swap for other reasons too.
Ask the engineer for the efficiency class of both units. That makes the running-cost gap concrete, rather than a vague sense that an old unit “feels” costly to run.
Weighing the repair bill against a new system
A repair quote should name what failed: a fan motor, a control board, or a gas leak. It should also say plainly whether the fix solves the root cause or just buys a few more months. One failed part is a very different case from a unit failing again and again. The questions every quote should answer applies equally to a repair estimate.
A new-unit quote, meanwhile, earns the same scrutiny as any first fit. It should give an itemised price for the unit, pipework and commissioning. A single-split swap typically costs roughly £1,500 to £3,000 fitted, based on the room and the fit itself.
That gives a firm number to weigh against a repair estimate. The same range applies whether the job is getting a unit fixed in Bath or anywhere else we cover.
Records that help the decision
Service records make this choice far easier. For systems holding 5 tonnes or more of CO2 equivalent, owners must keep F gas records for five years. These include gas added during maintenance and the results of leak checks.
A small home unit often falls below that threshold. Even so, keeping a note of each visit, the fault and the gas added is worthwhile. A pattern of repeat top-ups, for instance, points to a leak that a quick fix will not cure.
A rough guide, and its limits
As a rough guide, a newer unit with one fault is usually worth fixing. An older unit with repeat faults and a costly repair often does better replaced. Everything in between comes down to the fault and its cost.
A well-kept older unit can still outlast a poorly fitted newer one. Good fitting matters as much as age. Likewise, a hard-to-find part can make a small fix costly at any age.
The best answer comes from someone who has actually seen the unit. An engineer who checks the fault in person can say whether it stands alone or points to wider wear. No rough guide can do that from afar.
Getting a straight answer on your own system
If your unit needs help and you are unsure which way to go, our air conditioning repair service can help. One enquiry is checked, then passed on to one pre-qualified installer who covers your area and this kind of repair. Since the answer fits your own unit, it beats a rough guide.
That holds whether the address needs air conditioning repair in Plymouth or falls further out across the South West. A unit’s real state matters more than its age alone.
One enquiry puts you in touch with one pre-qualified installer for this job. It is free, with no obligation.
Submit your details once through our contact page. The installer who replies can tell you plainly whether a fix still makes sense — get in touch.
