I have a window well in a basement where I'd like to setup a portable AC unit (~10000 BTUs). There is a cover that I need to keep in place to avoid water collecting in the window well, but I could possibly keep this open a bit. How do I calculate the threshold for the exhaust of this hot air?
What are the external airflow requirements for portable and window AC units
air-conditioningcoolinghvac
Related Solutions
Often the actual pane unit for awning and casement windows can be removed (especially in newer and higher end windows). If this is the case, you can install a standard window air conditioner.
You would use an "L" shaped bar, called angle "iron" or angle stock (actually aluminum is probably more convenient), placed at the top of the unit instead of the upper sash to hold the unit in the frame.
The flat inside face of the angle iron would overlap and be screwed into the frame at the edges. The horizontal edge of the angle would be trimmed to fit inside the frame.
The air conditioner can be centered in the gap and the AC units side filler panels can be used to cover the gap. In the alternative, filler panels (clear plexi or any other thin weatherproof material) can be cut to fill the rectangular gaps on either side of the unit in place of the AC unit's fillers, which usually do not seal too well. In the alternative, the unit can be centered and one panel used to fill the gap. Be sure to seal around the AC edges and around the panels in either case.
Because most awning windows are not too tall, you may need a low profile AC unit such as this one
If your AC is seriously undersized, the compressor is probably already running 24/7 and blowing hot air into it won't make any difference. At max capacity an AC can remove a specific amount of heat from the air per hour. If you blow hotter air into the intake you will get correspondingly hotter air coming out. It's a zero-sum game.
In addition to closing off other rooms as others have suggested, here are things you might try:
- Block as much sunlight as possible from entering the rooms
- If you still have any old-fashioned incandescent bulbs, replace them. Ideally with LEDs, but compact fluorescents are cheaper up-front.
- Turn off any appliances you aren't using. If you need to run a small fan to properly circulate air that's OK, but you should be aware that the fans are generating heating and in that way they work against the AC, so it's a tradeoff. Some larger fans can use 100 watts or more of electricity, which is turned into heat. 100 watts of electric consumption generates about 350 BTUs/hour of heat.
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Best Answer
You would be far better off building a roof type structure over the window well that is well above the window well and projects far enough out around the edges of the well that rain water does not enter the well.
Trying to jury rig a scheme to keep an existing lid open "just enough" sounds like a recipe waiting for disaster. Either it will be left closed with the AC unit on and it will overheat and kill itself due to inadequate air flow. Or the lid will be left open an flood of water will enter the well and try flooding through the AC unit creating a potential safety hazard.