Tent Science 101

Tent Science 101

Looking for a small bedroom air conditioner that you can run without caring about electric bills?
It’s common sense: the smallest bedrooms are the least expensive to cool.
Your Igloo tent is your small bedroom and Close Comfort is your air conditioner.
The Igloo bed tent that comes with your Close Comfort small bedroom air conditioner is the result of years of engineering research and development.
It has been specially designed to feel spacious and be made from strong, light weight materials. It also had to be easy to set up and fold away, and above all, keep you cool through the night in the hottest bedrooms. Mosquito protection is also a key requirement.
It seems simple: the air conditioner provides cool air to the inside of the tent.
Knowing a little about your Igloo tent will help you get the best sleeping conditions through the summer.

Learn more about your Close Comfort Small Bedroom Air Conditioner

You may have noticed that the tent feels cooler at the bottom than at the top. The cool air is concentrate at the bottom to keep you as cool as possible while you sleep while minimizing the air conditioner electrical power consumption.

Here is a diagram showing how it works. The cool air from the AC flows from the foot end of the bed towards the pillow and then recirculates back to the air conditioner along the sides of the tent. The air flow from the AC has been carefully designed to minimize any mixing with the warmer air layers above.
In normal operation, it feels up to 12 degrees cooler at the bottom of the tent than outside in the bedroom. Cooling of the air by the AC contributes most of that difference, 8-9 degrees. The air flow past your skin contributes more apparent cooling, and reduction in water content of the air promotes sweat evaporation from your skin, giving that cool, dry feeling.
There’s lots of little surprises. Did you know that the temperature of the sheet is normally higher than the air just above? Measurements show that the air temperature about 25 mm above the bed sheet is about 1-2 degrees cooler! Why?
In a warm bedroom, heat radiation from the walls and ceiling warms the bed sheet surface, but does not directly affect the cool air. As the cool air travels from the air conditioner, over your body, and then returns along the side of the tent back to the air conditioner, it does get warmer. It picks up heat as it passes over the sheets, your body and along the warmer sides of the tent. If you touch the side of the tent, you will feel the warmth coming through.
Another useful hint: the greatest degree of air cooling occurs at the medium fan speed (the PC9 model runs only at this speed).
With the PC9+plus model, make sure you set the fan speed on “medium” to obtain the greatest cooling inside the tent. If you like to use “auto”, adjust the temperature setting till the fan speed is medium at a comfortable temperature.
Sometimes, the cool air flow can get diverted into the top of the tent. Look at the diagram below.

Here the tent adapter is draped over the cool air outlet, and the cool air “sticks” to the adapter fabric.
You can feel this if you place your hand near the cool air outlet.

This can easily happen if the AC is placed higher relative to the bed.
If this happens, you can rotate the cool air deflector downwards, till the air flow no longer sticks to the fabric.

Placing a light weight piece of Styrofoam between the cool air deflector and the adapter can help avoid this problem too.
Notice, however, that the jet of cool air is drawing in warmer air from higher in the tent. The best angle for the deflector may be even lower…

When the air conditioner is high relative to the mattress, it can perform better like this: air from the cool air outlet reaches the bed sheet surface quickly and less warm air mixing occurs.
When the weather gets really warm, can be worth experimenting with different arrangements of the AC to get the best performance.
If you like to eat breakfast in the tent, or “gup shup” with friends, try different deflector angles to see which works best for you.
Another trick, shown on one of our videos, is to throw a bed sheet over the top of the tent so it covers the pillow end of the tent.
In the hottest part of the summer, many of our users have told us they set up their tent on the roof of the house or on the ground floor where the air is a little cooler.
Being portable, it is so easy to move Close Comfort to where you use it.
Some people place their pillow at the air conditioner end of the bed in the hottest weeks of the year.

Is it worth insulating the tent sides?

Not really. We tested this. We wrapped bubble wrap around a tent in a hot bedroom and we only measured a slight temperature reduction. It’s worth remembering that despite it’s simple appearance, the behavior and exchange of air and warmth inside the tent is complicated. We don’t yet fully understand it ourselves.
Air exchange between the inside and outside of the tent is also really important for health reasons. This occurs through the top part of the tent where air can move freely through the netting.