Heating
Air conditioning in a British home does two jobs across the year. It keeps you cool through the warm months then switches round and heats you through the cold ones. The turn of the season from one to the other is the moment to give the system a little attention, because a few simple checks now mean reliable warmth right through the winter and a system that runs at its most efficient when you need it most.
None of this is complicated and much of it you can do yourself in half an hour. The rest is where a quick service pays for itself. Here is how to get your air con ready to heat before the cold really sets in.
Switching over to heat mode
Most people know their system cools but a surprising number never realise it heats too, and leave a perfectly good heater sitting idle all winter. The change is simply a setting on the remote or wall controller. You select heat mode rather than cool, set the temperature you want and the system reverses to pull warmth from outside and deliver it indoors.
When you first switch to heat there is often a short pause before warm air appears. That is normal. The system is bringing itself up to temperature so it does not blow cold air at you, and within a minute or two warm air starts to flow. If you are not sure which setting is which, the heat symbol is usually a sun and the cool symbol a snowflake. Get this right and half the battle is won.
A couple of other settings are worth knowing about while you are in there. Most systems have an auto mode that will switch between heating and cooling on its own to hold a set temperature, which sounds handy but in a British winter you are better off simply leaving it in heat so it is never tempted to cool. Many also have a fan speed setting. On the first cold day it is fine to run the fan a touch higher to warm the room quickly then drop it back to a quieter setting once you are comfortable. If your remote has a screen that has gone blank over summer, a fresh set of batteries before the season starts saves a fiddly moment on the first cold evening.
Cleaning the filters
If you do one thing before winter, do this. The indoor units pull room air across filters that trap dust, and over a summer of use those filters clog up. A blocked filter chokes the airflow, which means less warmth reaching the room, a harder-working system and a bigger bill for the same comfort.
- Open the unit. The front panel lifts or hinges open on most indoor units, revealing the filters behind it.
- Lift the filters out. They slide free easily and you will usually see straight away how much dust they have caught.
- Clean them gently. A vacuum over the surface or a rinse under lukewarm water does the job. Let them dry fully before they go back.
- Refit and close up. Slide them back the way they came and close the panel.
Do this every few weeks through the heating season if the system is working hard. Clean filters are the single biggest thing you control, and they make a real difference to both warmth and running cost.
It is easy to underestimate how much a clogged filter costs you. Every bit of dust blocking the airflow means the unit has to run longer and harder to shift the same amount of warmth into the room, so a neglected filter quietly pushes your bill up all winter while giving you less heat for it. A clean filter also keeps the air in the room healthier, which matters more in winter when the windows stay shut and the house is sealed up. Households with pets or anyone sensitive to dust should lean towards the more frequent end of the cleaning schedule. It takes five minutes and there is no reason to skip it.
Checking the outdoor unit
The outdoor unit is the part doing the heavy lifting in winter, drawing heat out of the cold air, so it needs clear space to breathe. Over autumn it tends to collect whatever the garden throws at it.
- Clear away leaves and debris. Autumn leaves pile against the unit and block the airflow it depends on. Sweep round it and lift anything resting against the grilles.
- Keep snow off it. After a heavy fall, clear snow from around and off the top of the unit so air can still pass through. Never chip at ice on the coils, just clear the loose snow around it.
- Give it room. Make sure plants, bins or stored garden bits have not crept up against it over summer. It wants a clear gap all round.
- Check it sits level and clear of the ground. It should be up off the floor so water drains away rather than pooling and freezing under it.
A smothered outdoor unit cannot gather the heat it needs, so this five-minute check matters more in winter than at any other time.
Understanding the defrost cycle
Here is something that worries people the first winter and should not. When it is cold and damp outside, a thin layer of frost can form on the outdoor unit as it draws heat from the air. To clear it the system runs a defrost cycle. It briefly reverses, warms the outdoor coil to melt the frost away then goes back to heating.
While this happens you might notice the warm air indoors pauses for a few minutes, the outdoor unit may steam a little as the frost melts and you could hear a change in the sound. That is all completely normal and it is the system looking after itself. It runs a defrost only when it needs one and it is over in a few minutes. Knowing it is coming means you will not mistake a healthy defrost for a fault. What you should not see is the unit frozen solid for long stretches, which points to a problem worth a call.
One practical point follows from the defrost cycle. The melt water needs somewhere to go, so make sure the ground under the outdoor unit drains freely and does not let a sheet of ice build up over a cold week. If the unit sits on a hard surface that puddles, a simple way to help is to keep that area clear so water runs off rather than pooling and refreezing under the feet. A unit standing in its own frozen melt water has to fight through more frost each cycle, which is exactly the situation good siting and a quick winter check are meant to avoid.
A service before the cold sets in
Filters and a tidy-up you can handle yourself. A proper service is where an engineer checks the things you cannot see, and the best time for it is autumn, before the system goes from light summer duty to heavy winter work.
- Refrigerant charge. The right charge is what lets the system move heat efficiently. We check it is correct and that there are no leaks.
- Electrical checks. Connections and controls are inspected so nothing is working loose or drawing wrong.
- Coil condition. Indoor and outdoor coils are checked and cleaned so heat transfers freely.
- Drainage. Condensate drains are cleared so there is nothing to freeze and block in a cold snap.
- Overall performance. We run it in heat mode and confirm it is delivering the warmth it should.
A serviced system heats harder for less money and is far less likely to let you down in the middle of January. It is a small bit of planning that saves a cold week waiting on a repair.
Setting your schedules
Winter is when thoughtful scheduling really pays. Rather than running the system flat out all day, use the timers and per-room control to put warmth where and when you want it.
- Warm rooms before you use them. Set the lounge to come up to temperature just before the evening and the kitchen before breakfast.
- Ease back overnight. Let bedrooms sit lower while you sleep and lift them before you wake.
- Heat only occupied rooms. Leave spare rooms off and bring them on only when they are in use.
A word of caution on one habit people bring over from radiators. With a slow wet system there was logic in leaving the heating ticking over low all day so the house never went properly cold, because it took so long to warm back up. A heat pump warms a room quickly, so that logic no longer holds. You are usually better off letting a room cool when it is empty and bringing it back up when you need it rather than holding it warm for hours with nobody there. Let the fast warm-up do its job and do not pay to heat thin air.
Because each unit is its own zone you have far more control than a single house thermostat gives you, and using it well is the difference between a comfortable efficient winter and a system left running pointlessly. It is worth spending ten minutes at the start of the season setting the schedules up to match your week rather than reaching for the remote every time you walk into a room. Once it is dialled in to your routine the house simply stays comfortable in the rooms you use at the times you use them, and you more or less forget about it. That set-and-forget comfort is one of the quiet pleasures of a well-sorted system, and it is also where a good chunk of the running saving comes from.
What good winter performance looks like
So you know your system is doing its job, here is what a healthy winter looks like. Rooms reach the temperature you set and hold it steadily. Warm air flows cleanly from the indoor units without odd smells or rattles. The occasional defrost cycle comes and goes quietly. The outdoor unit stays clear of heavy ice and runs without straining. Your bills look reasonable for the warmth you are getting.
If instead you find a room never quite warms up, the system struggles on cold days, the outdoor unit ices over and stays that way or you hear new noises, those are signs something needs looking at. Caught early most issues are small. Left through a hard winter they get bigger.
Keep half an eye on the little things as the season goes on. A faint musty smell when the unit first starts usually means the filters are due a clean. Warm air that is weaker than you remember points the same way or to a smothered outdoor unit. A system that cannot quite reach the temperature it used to hold might be low on refrigerant and worth a service call. None of these are cause for alarm if you catch them, and most trace back to the simple checks in this guide. The whole point of a bit of autumn preparation is that you spend the winter enjoying the warmth rather than wondering why it is not quite right.
Talk to Air Con North
A little preparation goes a long way, and the one part best left to an engineer is the pre-winter service. We look after systems right across Newcastle, Durham, Sunderland, Gateshead, Middlesbrough, Carlisle and the surrounding areas, and with over twenty-five years in the trade we know exactly what a North-East winter asks of your air con. Book a service now and go into the cold months knowing your system will heat reliably and efficiently when you lean on it. If you would like us to check yours over, or you are simply not sure it is set up right for heating, give us a ring on freephone 0800 246 5430. There is no obligation and we are happy to talk it through.
