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[How To]: Keep Your Aircon Cold

Everything you need to know to stay cool this summer.
Last updated: 2019-07-29

It’s rather warm outside; you may have noticed. This is why right now is the time to make sure your air conditioner is happy. There are a few simple bits of advice and maintenance tips that may prolong its life, reduce your electric bill and help your air conditioning blow colder.

DIY Solutions

The Filter

Let’s start at the beginning: the filter. Every air conditioner has one, and all the air that is blown into your house (and your lungs) passes through it. They can easily become dirty or clogged which could limit the A/C’s efficiency and pollute your house with dust.

If the filter is dirty, to the point of obstructing airflow, then the air that does get to your A/C can go straight into the guts of the machine (the evaporator coil) and damage the coil’s heat-absorbing capacity. This means your A/C won’t work as well as it should. A furry pet can also lead to pet hair blocking the filter.

What to Do About It

Clean it yourself. It’s pretty simple and doing so can lower the A/C’s energy consumption by 5-15%. That means your electric bill goes down.


Most filters are located in the return air duct. Wall-mounted units will have a panel on the front that you can easily lift open to expose the filter, which is the gauze/grid-y thing. If you have a standing machine or a vent in the ceiling, the filter will be where the air is being pulled from your space into the A/C. Depending on your unit, you may have to unscrew something, but the filter can be temporarily removed and cleaned or replaced completely, depending on the severity of the damage.

Before taking it out, be sure to turn off the electricity to the unit and the circuit breaker. The filter should easily slide out of the slot that’s keeping it in place allowing you to have a good look and inspect its condition. If you have a reusable filter, you can clean it by simply hoovering up the debris or spraying it with the shower and combing out the residue with a brush. Let it dry out before you slot it back in.

If you have disposable filters, replace them with the correct-sized filter. Buy them on Taobao by searching for 空调滤网 (kongtiao lv wang) or click here. You will need to know the brand name and model number of your A/C. This is usually on a sticker on the side of the machine.

The Coolant

Think of coolant as the fuel that keeps your A/C running. When it gets low, your air won’t be as cool. When was the last time someone topped up your coolant (this is not something you can do yourself)? If you don’t know, and your A/C is not getting as cold as it used to, it’s time to have a technician check.

What to Do About It

In Chinese, coolant is called yaoshui (药水) and the phrase for replenishing it is simple: jia yaoshui (加药水). Air conditioners come in different sizes and configurations, but most of us have split-units: one unit on the wall in a room and another square unit outside, connected by some tubes through a hole in the wall. Split-units come in different sizes, known in Chinese as pi (匹, rhymes with me). The smallest is one pi, going up to three pi, which you might see in a large office space.

How Much?

Prices for adding coolant go up depending on how many pi your unit is, but generally start around 200rmb these days. Once you learn to recognize the blue-green-colored steel tank (like a gas BBQ propane tank) that workers use to carry coolant around, you’ll begin to see them cruising around the city everywhere in summer.

And Then There’s This…

Be warned. Filling up the coolant requires the worker going outside your window to the outside unit, which is sometimes dicey. If you’ve seen pictures of daredevil A/C repairmen dangling from a seventh floor unit, they were probably filling up the coolant. This is standard practice for China. Worker safety isn’t a high priority. But what can you do? At least offer the poor guy a glass of water or something.

Get the Professionals

Repair and Maintenance

Lots of other things can go wrong. An ill-placed thermostat near a drafty window, on a sunny wall or near an oven can lead to your machine running too much and wasting energy. Your coolant might be leaking. Your exit pipe might be clogged. For all those scenarios, you’ll want to call the manufacturer’s maintenance hotline.

Here’s the contact info for some of the most common brands. No English though.

Gree (格力), 400-836-5315
Haier (海尔), 400-699-9999
Midea (美的), 400-889-9315
Panasonic (松下), 400-881-1315
Shinco (新科), 400-189-0315
Hisense (海信), 400-611-1111
Galanz (格兰仕), 400-830-0888

Professional Deep Cleaning

Something to consider, if you’ve never done it, is hiring a professional to do a thorough deep cleaning of your air conditioner to get the accumulated gunk out. It’s good for peace of mind, good for your health, and good for your air conditioner. There are foaming sprays available in almost every grocery store in Shanghai (空调清洁剂, kongtiao qingjie ji) that mimic what a professional would do (or here on Taobao), but, perhaps not surprisingly, professionals recommend against those, saying that you might actually damage the air conditioner. At best, they have limited effectiveness.

What Does a Professional Actually Do?

Their exact equipment and workflow may vary, but based on having this done to a colleague's air conditioner just recently, the broad outlines work like this.

The worker will open up the air conditioner and remove the filters, which either he or you will clean with water. Then they’ll put a kind of purpose-made bag around the wall unit (many made of medical-looking blue fabric) that has a drainage pipe on the bottom, and proceed to blast the gills of the internal A/C unit with pressurized water. Boom! The water blows out all the dirt and dust that has gotten up in there (it may be quite a bit), and the dirty water flows down the pipe and into some container. He then replaces the filters, puts anything he disabled or dissembled back into place, and hopefully cleans up after himself.

How Much Does It Cost?

We called the five companies below and they quoted us from 70-150rmb for a basic cleaning. If that’s not to your liking, there are dozens and dozens of these guys on Dianping, whom you can find by searching for 清洗空调 (qingxi kongtiao) or clicking right here.

Who Does It?

家电速修 (Jiadian Suxiu), 400 0099 737, 150rmb
轻松到家 (Qingsong Daojia), 400 8110 428, 85rmb per unit
十分到家清洗 (Shifen Daojia Qingxi), 403 8300 100, 72rmb per unit
专业空调清洗团队 (Zhuanye Kongtiao Qingxi Tuandui), 131 2070 7076, 78rmb per unit for service fee, 30rmb for call out service to Xuhui
e家政保洁家电清洗 (eJia Zhengbaojie Jiadian Qingxi), 400 6664 555, 89rmb per unit

Still Not Satisfied?

Then perhaps it’s time you went shopping for a new unit yourself. Stores like Suning and Gome are the places to go in person but maybe you’ve heard — some people actually buy things on the Internet. For that, Jingdong is probably your first stop. Gree is widely acknowledged by Shanghainese to be the best brand. As of this writing, a 1.5 pi Gree unit, good for 16-26 square meters, ran about 3,000rmb from dealers with good reputations and high sales volumes. On second thought, just call your landlord.