Air Conditioning Repair
Not cooling, leaking water, iced up or flashing an error code? We match you with vetted, F-Gas certified repair engineers across Surrey and the South of England — including rapid response for business-critical systems. Free quotes, no obligation.
Common faults and what they usually mean
Most breakdowns fall into a handful of patterns. Here is what each symptom usually points to — and which ones you can safely check yourself before calling anyone.
| Symptom | Most likely causes | DIY-checkable? |
|---|---|---|
| Running but not cooling | Dirty filters, blocked outdoor coil, low refrigerant (leak), failed compressor | Filters and outdoor unit only |
| Leaking water indoors | Blocked condensate drain, failed condensate pump, melting ice from a frozen coil | No — engineer visit |
| Ice on the indoor coil or pipes | Low refrigerant charge or badly restricted airflow (filthy filters) | Switch off, let it thaw, clean filters; if it re-freezes, it's a leak |
| Grinding, rattling or screeching noises | Failing fan motor or bearings, debris in the outdoor unit, loose panels | Visual check of outdoor unit only |
| Musty or bad smells | Mould on the coil and condensate tray — a hygiene issue, not a fault | Book a service with hygiene clean |
| Error code on display (F1 etc.) | Sensor, communication or refrigerant faults — codes vary by manufacturer | Note the code and model for the engineer |
Error codes are manufacturer-specific: the same code means different things on different brands, so always quote the code and the model number when requesting a repair.
What repairs cost
Repair pricing has two parts: getting a qualified engineer to the fault, and fixing it. A call-out with diagnosis typically costs £80–£150, with parts and any further labour on top. Simple fixes — a cleared drain, a condensate pump, a capacitor — are often completed within the first visit. Bigger jobs such as fan motors or control boards depend on parts availability for your model.
If the system has lost refrigerant, the work is a leak-find, a repair, and a recharge: expect £100–£300 for the re-gas element depending on the fault and how much refrigerant the system holds. For a full breakdown of leak-find, repair and recharge pricing, see our refrigerant recharge costs. Compressor replacement on an older unit is the classic repair-or-replace decision point — on a system past its tenth birthday the money is usually better spent on a modern unit.
| Item | 2026 cost |
|---|---|
| Call-out and diagnosis | £80–£150 |
| Leak repair and re-gas | £100–£300 |
| Parts (pumps, motors, boards) | Quoted per fault |
Indicative 2026 UK ranges. Refrigerant work is legally restricted to F-Gas certified engineers.
The truth about re-gassing
"It just needs a re-gas" is the most persistent myth in air conditioning. A sealed system never consumes refrigerant — if the charge is low, the refrigerant has leaked out, and simply topping it up means paying for gas that will leak out again while the underlying fault gets worse.
Three things every owner should know before paying for refrigerant work:
- The leak must be found and fixed first. A professional engineer leak-tests the system, repairs the joint, valve or pipe at fault, pressure-tests the repair and only then recharges to the manufacturer's specified weight.
- Venting refrigerant is illegal. Refrigerants are potent greenhouse gases. Releasing them deliberately is against the law, and recovery during repair work must be done with proper equipment.
- Only F-Gas certified engineers can do the work. Certification is a legal requirement for handling refrigerant. Everyone we match you with is vetted and F-Gas certified — if someone offers a cheap top-up with no leak test, walk away.
Repair or replace?
A well-maintained system should give well over a decade of service, but there is a point where repair money is wasted money. Use these tests:
Age. Under ten years old with a routine fault: repair. Past ten to twelve years, weigh any major repair — compressor, coil, control board — against the cost of a new system that will be more efficient and carry a fresh warranty. A new single split typically costs £1,800–£2,500 installed.
Refrigerant type. If your system runs on R22, replacement is effectively the only option — R22 is obsolete and cannot lawfully be recharged. Older R410A systems can still be serviced, but R410A is being phased down and refrigerant costs are rising, so a major R410A repair rarely makes sense. The UK F-Gas phase-down keeps tightening the supply of higher-GWP refrigerants year on year, which is exactly why R410A prices climb while R32 — a lower global-warming-potential refrigerant — is now fitted as standard on new systems, and some manufacturers are beginning to introduce even lower-GWP options. On an ageing unit, that trend quietly shifts the maths toward replacement.
Repeat failures. A second refrigerant leak, or a third call-out in two summers, is the system telling you something. Chronic faults on an ageing unit are the strongest replacement signal of all.
Running costs. Modern R32 units cool a typical room for roughly 18–23p per hour at 2026 electricity prices and heat efficiently too. If your old unit is visibly working harder than it should, an upgrade pays part of its own way. See installation options and costs.
Sources & methodology
- Repair pricing: 2026 UK call-out (£80–£150) and re-gas (£100–£300) ranges.
- Refrigerant law: venting is illegal; handling requires F-Gas certification; R22 can no longer be used for recharging.
- Running-cost basis: ~26p/kWh (July 2026 cap), 2.5 kW-class unit drawing ~0.7–0.9 kW.
Emergency and business-critical repairs
When a server room, restaurant, surgery or shop floor loses cooling, hours matter. Many engineers in our network prioritise business-critical callouts — tell us it's urgent in your quote request and we'll match you accordingly.
Frequently asked questions
Get your system fixed properly
Describe the fault once — symptom, error code, make and model if you have them — and compare quotes from vetted, F-Gas certified repair engineers near you.