Each of the brands will vary by the size of area they will cool, by how they need to be vented, their energy efficiency, and if they have any special features. Some will have remote control capability, programmable timers, specialized air filters and multiple operating modes.
Size is the most important factor to consider when selecting a free standing air conditioner. If it is too small, it will not cool the area you bought it to cool and if it is too large, then it will shut down before it removes the excess moisture which will leave your area damp and subject to mildew and mold.
Depending upon the size of the area you are trying to cool, here are some estimates of the size BTUs you will need:
- 1,700 sq ft w/8 ft ceiling ~60,000 BTUs
- 740 sq ft w/8 ft ceiling ~24,000 BTUs
- 500 sq ft w/8 ft ceiling ~14,000 BTUs
- 450 sq ft w/8 ft ceiling ~13,000 BTUs
- 400 sq ft w/8 ft ceiling ~12,000 BTUs
- 300 sq ft w/8 ft ceiling ~10,000 BTUs
- 200 sq ft w/8 ft ceiling ~9,000 BTUs
- 150 sq ft w/8 ft ceiling ~7,500 BTUs
Also, if you have any of the following you will need to increase the power and size of your free standing air conditioner:
- rooms with high ceilings
- rooms poorly insulated, like a workshop or a garage
- the climate is very warm or humid
- the area has heat-generating appliances or lots of windows
Venting the Exhaust
All free standing air conditioners will give off hot air as part of the cooling process. This hot air is usually vented out of the cooled area through a window, a door, a wall, or a drop ceiling. Most portable or free standing air conditioners will come with a kit to vent the exhaust. This kit will include the proper hoses and parts and will typically work with a window, door or a drop ceiling.
It is almost always possible to set up a portable air conditioner to vent the exhaust through a sliding glass door or a window. Depending upon the model, however, the exhaust kit may not cover the entire door or window. If this happens, then any gap must be covered with another solid material such as plexiglass and duct-taped into position so there is no leaking.
Free standing air conditioners can be either double or single hosed for sending the exhaust hot air out and pulling more air in to cool. There are some models which have both.
Dual-hose - the dual hose model brings air from the outside in through one hose and uses that air to cool the area. The hot exhaust air is then sent outside through another hose. Through this process, the dual-hose air conditioner does not create negative pressure in the room while it is cooling, although some models use two fans which can result in slightly higher energy costs.
Single-hose - the single hose model draws air from the internal space it is cooling, cools it and then returns it to the room. A small amount of this same air is used to cool the unit and then that air will be blown outside as exhaust through the unit's exhaust hose.
Condensation
Free standing air conditioners also act as dehumidifiers which means they also remove moisture from the air and collect it. Different models have different ways of handling this moisture collection:
collects in a bucket - The very simplest of portable air conditioners simply collect the moisture and water in a collection bucket which must be regularly emptied.
Pumps - Some models have condensation pumps which are separate accessories to help pump the collected water out through a drain hose.
Gravity drain - Any free standing air conditioner can be set up with a permanent water drain hose to continuously send the collected water to a floor drain or some other means of draining it off.
Self-evaporative - Some models are partially or completely self-evaporating which means they use their air conditioning exhausts to evaporate all or part of the water collected. Those that are partially self-evaporative may have to have the water manually emptied every once in a while if environmental conditions are especially humid.
Energy Efficiency
Free standing air conditioners are generally very energy efficient. This means they can help save money on the monthly electric bills, especially when it is hot and humid. Their efficiency is measured by their Energy Efficiency Rating (EER). The higher a models EER, the more efficient that model is. If a model has an EER of 10, that is going to be a pretty energy efficient portable air conditioner.
Power Requirements
Most free standing air conditioners use a regular household outlet with 120V and do not require and special wiring. However, if it is a commercial-grade unit, it may need a 220V outlet.
Noise
Portable air conditioners do make noise because they have a compressor system and fans that circulate and cool the air. Some people are not bothered by it, considering it is nothing more than background noise, while others find it irritating. If you think it might be a distraction, there are models with noise minimizing features including multiple speeds and a programmable timer.
Many models will list the decibel rating of each fan speed which will provide an idea of how loud the unit will be. Remember, though that the sound will be impacted by the size of the room and by furniture, carpet, and where the unit is located relative to who is listening.
Maintenance
Free standing air conditioners generally require little maintenance other than what is typically done with permanent air conditioner units. Routine maintenance tasks with a portable air conditioner unit include:
- before storing the unit, ensure it is completely drained
- if it ices, defrost it completely
- Install it correctly to ensure maximum operating efficiency
- Install new or clean the air filters at least once every summer
A free standing air conditioner is a good option if your home or office needs supplemental cooling, but not an entire new air conditioning system. These units are portable and can be moved from area to area and used wherever there is a need for cooling and then easily stored when not in use.
