Ductless Air Conditioning and Heat Pump FAQ

How does an air conditioner work?

An air conditioner works by transferring the heat from the indoor air to the outside and transferring the coldness from the outdoor air to the inside. Transferring the actual air would be highly inefficient, so air conditioners utilize a refrigerant along with components such as a compressor and expansion valve to get the maximum performance out of temperature differences between the inside and outside.
More information on how the refrigeration cycle works can be found at:

• Air conditioners - Wikipedia
• Vapour-compression refrigeration cycle - Wikipedia

What are the main components of a ductless air conditioning system?

A ductless air conditioning system includes an outdoor unit, indoor unit(s) and line-sets connecting them. The outdoor unit includes the condensing coil, the compressor, the expansion valve and a fan to cool the condenser coil. The indoor unit includes the evaporator and a fan for airflow. The line-sets connecting the indoor and outdoor units are made up of heat insulated copper tubing for transferring the refrigerant.

Is there any air exchange between the indoor and outdoor units?

No, the line-sets provide only refrigerant (R-22 or R-410A) exchange between the indoor and outdoor units. The refrigerant used in most current systems is R-22 with R-410A replacing R-22.

Is a ductless air conditioner more efficient then a central air conditioner?

In most cases, yes. The evaporator is placed close to the ceiling and since colder air is more dense then hot air, the cold air will naturally drop allowing the air conditioner to utilize its maximum cooling capacity. Unlike central air conditioning systems, the evaporator unit is placed in the basement above the furnace, which needs to push the cold dense air up to the second or third floor. In central systems most of the air will travel through the shortest runs creating a cold basement, a fairly cool 1st floor, usually unsatisfactory conditions on the 2nd and 3rd floors.
One effective solution for this problem is to install butterfly valves in all the main ducts to control the airflow pattern.

Is one ductless air conditioner able to cool the whole home?

Yes, if the indoor unit is properly placed such as at the top of the stair landing on the second floor, then the airflow can be adjusted to completely cool the 2nd floor and the remaining cool air travels down the stairs to the 1st floor. Through natural convection, the whole home can be cooled quickly. Hundreds of homes without ducts in Toronto have been cooled with only one unit!

Are ductless heat pumps available?

Of course! Ductless heat pumps are available from a number of different manufacturers such as Panasonic, Mitsubishi etc. and are as efficient for heating as they are for cooling. This is because heat pumps use the same cycle as air conditioners except it is reversed, transferring the available heat from the outside to the inside.

Can ductless heat pumps be utilized in Toronto?

Definitely, the average minimum temperatures in Toronto for the months of January and February are approximately -7°C. Also the number of days in the year where the minimum temperatures are below -10°C is only around 26 days. These are also minimums, meaning the daytime highs are usually higher. By choosing the right system with a low ambient cooling/heating option, you will be able to heat your whole home with just the ductless heat pump for most of the winter days.

Can I still use my R-22 equipped ductless system?

Of course, most of the residential and commercial air conditioning units (up to 2006) use R22. It will take some time for those units to be replaced with R410A compatible units. According to the Montreal Protocol, refrigerant maintenance for commercial and residential R22 air conditioning units will be allowed until January 1st, 2015. After that date, the unit will be allowed to be used but refrigerant maintenance (such as recharges) will not be allowed (other maintenance is allowed). However, if the air conditioning unit was installed properly then no refrigeration leak should develop, allowing for many decades of enjoyable use.

How long can a ductless air conditioner last?

The people at ductless.ca Inc. have been installing ductless units in the Toronto area since the mid 1980's and only a few of those units have been replaced due to defective components. Most are still running just as well as the day they were installed. If the unit is properly maintained then you can expect more then 20 years of life.

Troubleshooting

What maintenance and service do ductless air conditioners require?

It is very important to keep the indoor unit filters clean. These filters are located in front of the evaporating coil behind the front cover. Some ductless units include smaller black charcoal filters which are required to be dusted off and then exposed to sunlight for at least 8 hours every 6 months in order to properly function. The charcoal filter usually last for 2 seasons (24 months). Also, some ductless air conditioner include Catechin filters which are also required to be cleaned regularly and replaced every two seasons (24 months).
The outdoor units also need to be cleaned regularly, especially the coil which can trap leaves, dust, etc. All that is required is a soft brush (as to not damage the coil) and sweep the coil until it is relatively free of any obstructions.

Why is my indoor ductless unit not blowing the same amount of air as before?

Reduced air flow will also be caused by dirty filters, if the filters are clean then make sure the indoor unit fan is clear of any obstructions and that the leading edges of the blades are not covered with dust, mold etc. Determining if the blades are dirty is relatively straight forward, just straighten out the air-flow vanes and using a flashlight look through the vanes and the fan should be visible. The blades can be cleaned using compressed air. For more stubborn dirt, the fan might have to be removed from the indoor unit and cleaned more rigorously ductless.ca Inc. does provide this service.

Is there any other maintenance or service that might have to be performed?

As with other household appliance, the indoor and outdoor units should be cleaned and inspected regularly. One other notable issue which might arise is with the line-set insulation. During the summer, animals such as raccoons and squirrels sense the moisture underneath the insulation and might bite at the insulation to access the water. This is obviously easier for the animals if the line-sets are placed horizontally such as on a flat roof as opposed to vertically against a wall. The missing insulation should be replaced as soon as possible in order to reduce line-set corrosion, and maintain air conditioner performance. ductless.ca Inc. provides line-set insulation replacement service.

If my remote control is not working or I cannot find it, can I still use my air conditioner?

Yes, most units have an emergency button on the indoor unit. Once this button is pressed the unit will go into emergency mode, maintaining 24°C until the button is pressed again, or the remote control is found/replaced and activated.