Air Conditioning Frequently Asked Questions

Everything you ever needed to know about air conditioning. Can’t see your question? Send it through and we’ll update our FAQ right away!

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  • Do you have any warranties?

    All units, parts and workmanship, are covered by a minimum one-year warranty. A guarantee of up to ten years is, however, available on all systems that The Air Conditioning Company installs provided that you have a planned maintenance program in place, and the units are serviced accordingly.

  • Why is my air conditioner leaking?

    There are several reasons why your system is leaking water.

    The condensate that is produced in the coils on the indoor part of your system should fall into a drip tray which is either drained away by gravity or pumped outside.

    If excess water is finding its way down your wall then it’s more than safe to assume that much or all of the condensate is not being drained away.

    Sometimes the drain hole might clog up with dirt, so the water obviously finds the easiest route to drain away which can’t be anything other than down your wall! However, if the condensate is being drained away with help from a pump, then there is every probability that the pump may have failed and this will obviously need replacing quickly. So often we find that the coils in the system have been so caked up with dirt that it has ended up blocking the unit drainage system.

    A leak can be caused by something as simple as a dislodged drainage pipe, making the water drain upwards, which, of course, eventually flows back into the unit and down your wall. In this case, it’s a simple matter of correcting the angle of the drainage pipe.

    Finally, and in more serious cases, should the system have leaked a large quantity of refrigerant, this will cause the coils on the indoor unit to “ice up” which will also result in leakage when the ice melts. If you do see ice on the coils, it is vital to switch the unit off immediately and call your air conditioning engineer.

    Finally, and I’m sorry to hammer the point home as I have in our other videos, but so many of these problems would not happen if your unit was regularly maintained.

  • Do you repair air conditioning systems you did not install?

    Yes. We regularly repair air conditioning systems that were installed by other companies. In fact, many customers first come to us for a repair and then stay with us for ongoing maintenance or eventual replacement. The important thing is whether the system is worth repairing, not who originally fitted it. We are always happy to assess it honestly and tell you whether repair is sensible, economical, and likely to give you a reliable result.

  • What kinds of fitted air conditioning faults do you repair?

    We deal with a very wide range of fitted air conditioning faults. That includes units not cooling or heating, water leaks, icing, noisy fans, failed condensate pumps, electrical faults, controller problems, communication faults, refrigerant leaks, sensor issues, and general poor performance. Some repairs are simple and quick, while others need deeper diagnosis or parts. Our job is to find the real cause, explain it clearly, and recommend the most sensible next step.

  • My air conditioner runs but does not cool properly. What could be wrong?

    There are several possibilities. Common causes include dirty filters or coils, incorrect settings, poor airflow, low refrigerant caused by a leak, fan or sensor issues, or a system that is struggling with the heat load in the room. The important thing is not to jump straight to one conclusion. Proper diagnosis matters, because the fix for a dirty system is very different from the fix for a refrigerant leak or a failing component.

  • My unit is leaking water. What should I do?

    If the leak is significant, turn the system off and protect anything below it. Water leaks are commonly caused by blocked drains, dirt in the condensate system, failed pumps, or icing that later melts. Some are simple, some are not, but they should not be ignored because water damage can quickly become the bigger problem. Our engineers see this issue all the time and can usually tell quite quickly whether it is a maintenance matter, a repair, or a bit of both.

  • My unit has iced up. Should I turn it off?

    Yes - in most cases it is best to turn it off and let it thaw before an engineer attends, unless we advise otherwise. An iced-up unit often points to poor airflow, dirty filters, fan problems, low refrigerant, or other underlying issues that need proper diagnosis. Leaving it running rarely improves the situation and can make fault-finding harder. Once thawed, we can inspect it more accurately and work out the true cause rather than just dealing with the symptoms.

  • My system smells stale or musty. Is it broken?

    Not necessarily, but it does mean something needs attention. A stale or musty smell is often caused by dirt, moisture, and bacterial build-up on the coils or in the drain system, so a deep clean or service may solve it. If the smell is burnt, electrical, or still there after cleaning, then it should be treated as a repair investigation. Smells are useful clues, but the underlying cause has to be confirmed properly.

  • My system is noisy or rattling. What does that usually mean?

    Noises can come from several places. It could be something simple like a loose panel or vibration, or it could point to fan motor wear, a failing condensate pump, compressor-related issues, or pipework movement. The key point is that new noises are worth investigating early. Small mechanical issues often get more expensive if they are ignored. We would much rather catch a rattling component early than wait until it turns into a major breakdown.

  • The breaker keeps tripping. Can I keep resetting it?

    No. If the breaker keeps tripping, the system should be investigated rather than repeatedly reset. Persistent tripping may point to electrical faults, motor problems, component failure, moisture ingress, or other issues that should not be ignored. Resetting it over and over can make the situation worse and is not good practice. We can diagnose whether it is a relatively simple electrical issue or something deeper within the system.

  • Can thermostat or controller settings make a system look faulty?

    Yes - very often. Wrong mode selection, an unexpected timer setting, fan-only operation, setpoint errors, or controller confusion can all make a healthy system look faulty. It sounds obvious, but checking the controls properly is one of the most common first steps in diagnosis. The good news is that if the issue is a settings problem, it is usually quick to resolve. The bad news is that many people assume the system is broken before the basics have been checked.

  • Can you diagnose error codes?

    Yes. Error codes are very useful because they point us towards the affected circuit or operating condition, but they are a starting point rather than a final diagnosis. A good engineer will still test, inspect, and confirm the real cause before replacing parts. We are happy to work from an error code if you have one, and it is always helpful if you can tell us the make, model, and exactly what appears on the controller.

  • Can low refrigerant just be topped up?

    No. Refrigerant should not simply need topping up in a sealed system. If the charge is low, there is usually a leak somewhere that needs to be found and repaired properly. A simple top-up without addressing the cause is usually false economy and can lead to a repeat failure. We will always look for the reason the charge has dropped rather than pretending the gas has just disappeared on its own.

  • What happens during a repair visit?

    A repair visit starts with diagnosis. We inspect the system, listen to the symptoms, check settings and operation, and test the likely fault areas before confirming what is wrong. If the issue can be resolved there and then, we do that wherever possible. If parts are required or the repair is more involved, we explain the findings and provide a clear quotation before additional work is carried out. No surprises, no guesswork, and no unnecessary parts changing.

  • What information should I give when I book a repair?

    The more detail you can give, the better. Useful information includes the make and model, how many units are affected, what the system is or is not doing, any error codes showing, whether it has been serviced recently, and whether the fault is constant or intermittent. Photos can help too. Good information makes diagnosis faster and gives us the best chance of bringing the right expectations and, where possible, the right parts.

  • How quickly can you attend a repair?

    Response time depends on urgency, location, and current workload, but we always try to attend as quickly as practical, especially for businesses, server rooms, or sites where cooling is critical. We cover London and the surrounding area for fitted-system repairs and understand that some breakdowns simply cannot wait. Even when an immediate visit is not possible, our team can often help with sensible first checks and set expectations clearly so you know where you stand.