Maintenance
Air conditioning rarely dies without warning. In our experience the units that break down completely almost always gave off signals for weeks or months beforehand, signals the owner either did not notice or hoped would go away. They seldom do.
The good news is that a fault caught early is usually smaller, cheaper and less disruptive to put right than the same fault left to fester. This guide runs through the signs that your air conditioning needs attention, what each one tends to mean and, importantly, when you should stop using the system and call an engineer rather than carry on regardless.
Weak or warm airflow
The most common complaint we hear is simply that the system is not cooling, or heating, the way it used to. The air coming out feels feeble or the room takes an age to reach temperature. Sometimes the air is barely cool at all.
Weak airflow often points to something restricting the system. A badly clogged filter is the first suspect and the easiest to check. Beyond that it can mean a dirty coil, a failing fan or a problem with the refrigerant charge. Air that will not reach a comfortable temperature at all, especially if the system seems to be running normally otherwise, frequently signals a refrigerant leak. That is a job for an engineer, both to find the leak and to recharge the system correctly under F-Gas rules.
It is worth saying that simply topping up refrigerant is not a repair in itself. If a system is low on gas it is because the gas has escaped somewhere, and the right approach is to find and fix that leak rather than keep refilling a system that will only run flat again. Any engineer who offers to just gas it up and send you on your way without investigating is not doing you any favours. Beyond the cost, the F-Gas Regulation is clear that leaks should be repaired rather than ignored, so the proper job is always to track down the cause.
Odd noises
A healthy system is quietly unobtrusive. New or louder sounds are worth taking seriously because each tends to mean something specific.
- Rattling or buzzing. Often a loose panel, a failing fan bearing or a component that has worked itself loose with vibration.
- Grinding or screeching. Usually a sign of a motor or bearing wearing out. Caught early it is a part swap, left too long it can take the motor with it.
- Clicking that does not stop. A single click as the system starts is normal. Persistent clicking can point to an electrical or control fault.
- Gurgling or hissing. Can indicate refrigerant moving where it should not, which may mean a leak.
If a noise is sudden, loud or accompanied by the system cutting out, switch it off and call us rather than letting it run.
Bad smells
Your nose is a surprisingly good diagnostic tool. A musty or earthy smell when the system runs almost always means mould or bacteria growing on a damp coil or in a blocked drain. It is unpleasant and it is not something you want blown around a room full of people, so it wants cleaning properly.
A sharp, acrid or burning smell is more serious. That can mean an electrical problem or overheating component. If you ever smell burning, turn the system off at the isolator and do not use it again until an engineer has looked at it.
There is also what people sometimes describe as a dirty-sock smell, which tends to appear on start-up and fade after a while. It is caused by bacteria building up on a damp coil, and it is more than just unpleasant, it tells you the system is overdue a proper clean. A deodorising spray from a shop will mask it for a day or two at best. The only real fix is to have the coil and drain cleaned properly, which is part of a full service.
Water, leaks and ice
Air conditioning produces condensation as a normal part of its work, and that water is meant to drain away out of sight. When you see water dripping from an indoor unit or pooling beneath it, the drainage has usually blocked or the drain pan has an issue. Left alone it can stain walls, damage ceilings and feed the kind of mould that causes those musty smells.
Any oily residue around pipework or the outdoor unit is a different matter. That can be a sign of a refrigerant leak rather than water and should be checked by a qualified engineer promptly.
Ice on the pipes or unit
Ice forming on the refrigerant pipes or on the indoor coil is never normal, even though it sounds like the system is just being cold. It usually means airflow is restricted, often by a filthy filter or failing fan, or that the refrigerant charge is low. The ice makes things worse by blocking airflow further, so it tends to snowball.
If you spot ice, turn the system off and let it defrost fully. Check and clean the filters. If it ices up again once it is back on, stop using it and call an engineer, because running a system in that state can damage the compressor, which is the most expensive part to replace.
Short-cycling and odd behaviour
A system that switches itself on and off every few minutes without ever settling is short-cycling. It is hard on the components, poor for comfort and wasteful of energy. Causes range from a faulty sensor or thermostat through to refrigerant and control problems. It is a classic sign that something is not right internally and wants diagnosing.
Along the same lines, watch for a system that will not respond to the remote, keeps tripping the electrics or displays warning lights. None of these are things to live with.
Before you assume the worst with short-cycling, it is worth ruling out the simple causes. A unit fitted in direct sunlight, sat above a heat source or in a spot where the warm air it puts out blows straight back over its own sensor can switch itself on and off because it keeps misreading the room. Draughts from an open door or window near the indoor unit can do the same. If none of that applies and the system still cannot settle, it is an internal fault that wants diagnosing rather than something you can cure by moving the furniture.
Rising bills and error codes
Sometimes the clearest sign is on paper rather than in the room. If your energy use has crept up without you running the system any more than usual, it is losing efficiency somewhere, perhaps to a dirty coil, a worn component or a slow refrigerant leak. The system is working harder to deliver less.
Modern units often help you out by flashing an error code on the indoor unit or remote when they detect a fault. It is well worth noting down exactly what the code is before you call us, because it gives the engineer a head start on the diagnosis. Do not assume a code will clear itself, it is the system telling you it has found a problem.
Be a little wary of simply resetting a system that keeps throwing the same code. A single reset after a one-off glitch is reasonable, but if the fault returns straight away the code is doing its job and warning you of something real. Clearing it over and over just to carry on using the unit can let a minor problem run on until it causes damage. The code is a symptom, not the illness, and the sensible response is to have the cause looked at rather than keep silencing the alarm.
What you can check first
Before you pick up the phone there are a few safe checks that occasionally solve the problem outright and always help us help you faster.
- The filters. Lift the cover and look. A thick mat of dust restricts airflow and causes a surprising number of the symptoms above. Cleaning them is safe and often enough on its own.
- The settings. Check the mode and temperature on the remote. It is easy to leave a system in the wrong mode or set to a temperature that will not call for cooling or heating.
- The outdoor unit. Make sure it is not blocked by leaves, rubbish or overgrown plants and that nothing is leaning against it. It needs clear air around it to work.
- The power. Check the system has not simply tripped a breaker. If it keeps tripping, though, leave it off and call us.
Those checks are the limit of safe DIY. Anything that involves opening the sealed parts of the system, touching the refrigerant or poking around the electrics should be left to a qualified engineer. If the simple checks make no difference, do not keep tinkering in the hope of fixing it yourself, as that is usually how a small fault turns into a bigger one. Note what you found, leave the system off if anything seems wrong and give us a ring.
When to turn it off and call us
Most faults can wait a day or two for a booked visit. Some should not. Switch the system off at the isolator and call straight away if you notice any burning smell, smoke, water dripping onto or near electrics, repeated tripping of the breaker or ice that keeps returning after a defrost. In those cases running the system risks turning a repair into a replacement, or worse.
For everything else the rule is simple. If something has changed and it has not gone away, it is worth a call. Problems with air conditioning tend to grow, not shrink, so the early phone call is nearly always the cheaper one.
When you do call, a little preparation helps us help you. Have the make and model of the unit to hand if you can, note down any error code showing on the display and be ready to describe when the problem happens and what the system is doing at the time. Is it worse on start-up or after hours of running, on cooling or on heating, all the time or only now and then. Those details often let an engineer arrive with a good idea of the likely cause and the right parts already in the van, which means a quicker fix and less back and forth.
It also pays to resist the temptation to keep nursing a system that is clearly struggling. Running a unit that is iced up, low on gas or making an ugly noise in the hope it will see out the week is how a modest repair turns into a replaced compressor. The compressor is the heart of the system and by far the most expensive component, so protecting it is always worth a short spell without cooling while you wait for a visit.
Talk to Air Con North
If your system is showing any of these signs, we would rather hear about it sooner than later. Our F-Gas registered engineers cover homes and businesses across the North-East, from Newcastle, Gateshead and Sunderland to Durham, Middlesbrough and Carlisle, and we will diagnose the fault honestly and tell you plainly what it needs. Call us free on 0800 246 5430 to book a repair visit or simply to describe what your system is doing and get our advice.
