Air Conditioning Questions Answered

When something doesn’t seem quite right with your air conditioning, the first question is often a simple one:

Is this normal, or do I need an engineer?

As Oxford Air Conditioning’s Service Desk Manager, Matt Pike helps customers with questions like these every day — from systems that don’t appear to be cooling properly to unusual noises, leaks and servicing queries.

For the first in our Ask Oxford Air series, we asked Matt to answer five of the questions our service team hears most often.

1. My air conditioning isn’t cooling as well as it used to. What should I check first?

Matt:“The first thing I’d usually suggest checking is the filter.

If the filters haven’t been cleaned for a while, dust can build up and restrict the airflow through the indoor unit. That can make the system feel as though it isn’t performing as well as it should.

Also check that the system is actually set to COOL mode, that the temperature setting is sensible and that doors and windows aren’t being left open while it’s running.

If you’ve checked those basics and the system still isn’t cooling properly, that’s the point where it’s worth giving us a call. There could be another issue that needs an engineer to investigate.”

Before calling, check:

• Is the system in COOL mode?

• Is the selected temperature below the current room temperature?

• Are the filters clean?

• Are doors and windows closed?

• Does the airflow feel weaker than usual?

If everything looks right but performance has noticeably reduced, don’t simply keep lowering the thermostat.

2. Does setting the air conditioning to 16°C make the room cool faster?

Matt:“No — and that’s probably one of the biggest misunderstandings we come across.

If the room is hot, setting the system to 16°C doesn’t normally mean it’s going to cool the room any faster than if you set it to 22°C.

You’re basically just telling the unit to keep cooling until it reaches a much lower temperature.

I’d recommend setting it to the temperature you actually want the room to be and letting the system do its job.”

For most homes and workplaces, somewhere around 21°C to 24°C is a sensible starting point.

Setting the temperature extremely low can result in unnecessary operation without delivering the instant cooling people sometimes expect.

3. My indoor unit is dripping water. Is that normal?

Matt:“Air conditioning naturally produces condensation when it’s cooling, but that water should be taken away through the drainage system.

Water coming out of the indoor unit and into the room isn’t something I’d regard as normal.

Sometimes it can be something relatively straightforward, such as an issue with the drain, but it needs looking at rather than just putting a towel underneath it and carrying on using the system.”

If you notice:

• Water dripping from the indoor unit

• Damp patches around the system

• Water marks appearing on a wall

• Recurring leaks

it is sensible to arrange an inspection.

Continuing to operate a leaking system could potentially cause damage to the surrounding area as well as allowing the underlying problem to continue.

4. My air conditioning smells strange when I turn it on. What does that mean?

Matt:“A musty smell is often a sign that the unit needs some attention.

Filters are always worth checking, but smells can also come from dirt or moisture elsewhere inside the indoor unit, so cleaning the filter doesn’t always solve it.

If the smell keeps coming back, I’d recommend getting the system professionally cleaned and inspected.”

Air conditioning should not normally produce a persistent unpleasant smell.

If the smell is unusual, strong or accompanied by other symptoms such as poor performance or unusual noises, switch the system off and seek advice.

Avoid spraying household cleaners or fragrances directly into the unit.

5. How often should air conditioning be serviced?

Matt:“That really depends on the system and how much it’s used.

A domestic unit that’s used occasionally isn’t the same as a system running for long periods every day in a commercial building.

What I would say is that servicing shouldn’t only happen when something goes wrong.

Regular maintenance gives us the chance to clean and inspect parts of the system the customer can’t access, check how it’s operating and spot developing problems before they turn into breakdowns.”

Commercial installations may require planned preventative maintenance at regular intervals, particularly where the equipment is important to the operation of the business.

For domestic systems, the appropriate servicing schedule will depend on factors including:

• Frequency of use

• Type of system

• Manufacturer recommendations

• Environment

• Age and condition of equipment

If you’re unsure when your system was last serviced, our service team can advise.

Bonus question: Can I use my air conditioning for heating?

Matt:“Yes — with most of the modern systems we install, absolutely.

A lot of customers still think of air conditioning as something that’s only useful during hot weather, but many systems are air-to-air heat pumps, so they can provide heating as well.

If you’ve never used HEAT mode before, autumn is actually a good time to try it rather than waiting until the first really cold day.”

When changing to heating mode, remember that it is normal for some systems to take a short time before warm air begins to flow.

When should you stop troubleshooting and call us?

There are plenty of simple things customers can safely check themselves, but Matt’s advice is not to dismantle equipment or continue operating a system when something clearly seems wrong.

Contact an air conditioning engineer if you notice:

• A significant loss of heating or cooling

• Water leaking indoors

• Persistent unpleasant smells

• Unusual rattling, buzzing or grinding

• Error codes or warning lights

• The system repeatedly switching itself off

• Very weak airflow despite clean filters

• A fault that keeps returning

Early advice can often prevent a minor issue from becoming a larger problem.

Ask Oxford Air

Our Ask Oxford Air series answers the questions customers regularly ask our engineers and service team, helping you understand your system and know when professional help is needed.

If there’s something you’d like us to cover in a future guide, let us know.

Need help with your air conditioning?

Matt and the Oxford Air service team support domestic and commercial customers with servicing, maintenance, fault diagnosis and repairs.

If your system isn’t performing as expected, or you would like to arrange a service, get in touch with Oxford Air Conditioning and our service team will help you decide the best next step.