A couple of useful tidbits (some only marginally related to the OP):
The part of the unit that expects to be “inside” isn’t waterproof. This is usually where the controls are, as well. If there’s any chance it will get rained on where it is, be sure to tape around places like where the front plastic meets the metal case of the unit, and tape a sheet of clear plastic over the control panel (if electronic) or come up with an alternative if the unit is old-style and has knobs. Also arrange some way for water to run off instead of getting in where you’ve attached your ducts.
An air conditioner in tip-top shape should be able to chill air down to 20 degrees below the intake temperature. Anything less than 15 is marginal.
Air conditioners don’t work when it is cold outside. They work by evaporating a liquid in the inside coil and condensing it via the outside coil - that reduces the temperature to the point where it can be compressed back into a liquid by the compressor. Note that this is a compressor, not a pump (big difference)! If it is cold enough outside that the gas condenses in the outside coil, the compressor will be damaged (liquids aren’t compressible).
Similarly, if the outside coil is too hot (generally only from crud building up on the fins) the system will have high pressure. When this happens, it won’t cool as efficiently (see point #2), the electric usage will skyrocket, and you’ll hear the unit being unhappy - a “pu-waaaaaaaaah” when the compressor starts and a "kerplunk"when it stops. And it may stop from a safety switch and not because it thinks it is cool enough inside.
If you need to use an extension cord, make sure it is a heavy duty one. For a regular wall-socket type plug, look for one that is made with “number 14” wire (smaller numbers are bigger wires). If your unit requires a special outlet, match the wire size emboosed/printed on the unit’s power cord.
It’s well away from anywhere it might be rained on, and the electrical cabling is all outdoor-rated.
The only thing that remains now is to locate where the condensate is supposed to drain from - it’s not easily visible as in order AC units I’ve seen, and there doesn’t appear to be a fitted outflow thingy to attach a drain tube to, either. I noticed this morning that the bottom of the unit is currently full of water, so I’ve left if off for today. At worst I’ll probably just put a couple of shims underneath it so it’s raised up enough to drain - the design of our balcony is such that any water on it drains to an eaves trough. It was draining onto the floor before yesterday, but I rotated it 90 degrees and that seems to have blocked it. (The original orientation was intended to point what I had moronically assumed were “intakes” on the back into open air.)
Many modern units are designed without drain holes - the fan is supposed to pick the water up from the bottom and throw it onto the outside coils to cool them down when the water evaporates. Those are called “slinger fan” designs. But it should definitely not be full of water, and you should hear a swishing as the fan blades dip into the water.
That’s what I would do. Put a few shims under the front end so that’s tipped back just a hair. The water will go wherever it needs to go. If there’s a drain, the water will find it, if there isn’t either the fan/heat in the unit will take care of it or it’ll overflow.
Thanks, again - I am fairly certain mine is one of these. It is definitely sounding wetter than it usually does - I think it’s probably just not quite level and pooling a little deeper by the fan blades. Shims it is.
You know a lot about A/C - do you work with HVAC for a living or have you just picked it up through being considerably less dense than Mudd?
Hi! The manuals for both of my window units say they should be tilted at a 5-degree angle for proper drainage. I imagine yours would be the same. Hope that helps!
And of course, by increasing the pressure, you’re also increasing the boiling point of the water. So that plus the salt means your pasta will cook in a matter of seconds.
Nitpick…increased pressure increases the boiling point of water. However, salt will also increase the speed at which the coils rust…so keep it out of the AC.
It is important when understanding AC and refrigeration systems to realize that these machines do not create cold, that is impossible, they only remove heat.
The window units circulate inside room air through the unit, drawing off the heat and placing the heat outside and returning the cooler air to the inside. Your refrigerator works the same way, by removing heat from inside the box and slightly warming up the outside of the fridge and inside of your kitchen.
If you think in terms of removing heat you can better understand how to cobble together something that may work for you. It sounds llike you were attempting to remove heat from the outside air and place cold air into the room, and that isn’t going to work. Think in terms of moving the heat out of the room instead.
I do get this - I have explained it to people in the past. Only makes it more embarrassing.
Of course, recirculating and re-cooling the same air makes perfect sense and my misunderstanding of this is definitely palm-to-face. I didn’t really think it through (as is probably evident) and I think I may have been thrown a little bit by the intake & exhaust hoses on portable units. While we’re on the subject, why is there this apparent difference?
The filter is just to catch dust. The unit is engineered to fit directly into a wall or window. Putting it outside and ducting it to the room causes air friction that was never accounted for. Plus, it was never intended to have the entire unit outside from a weather standpoint. But, redneck engineering is a whole other type of thinking. If no one cares, take off the duct and put it in the window AFTER you clean out all of the coils and the the fins with a real thin brush or some compressed air. Hey, ya can’t hurt anything, right?
I’ve worked at / managed / designed large computer rooms since 1976, mostly for stingy places that wouldn’t pay for 24-hour service for the air conditioners (but they would for the computers - go figure). I became adept at diagnosing problems, performing many repairs, and learning to tell when the repair people are BS-ing me.
Rather than putting the A/C unit outside and ducting the intake and outflow, would it work to put the unit inside and run a single duct from the back of the unit to the outside air?
The only problem I can see is that you might not have enough airflow for that to work properly.
No, that wouldn’t work. First off you wouldn’t have proper airflow without a more complex set of ducts. Window units intake air from the back and exhaust it from louvers on the side. You would need one big duct for the coil and then a separate duct for each side louver. If you just made one big shroud for the entire thing it would just circulate the same air over and over. Second, you’d have to deal with the heat. AC units get really hot. Between the duct work and the unit itself, there would be a lot of heat dumping into the room, you’d have to find a way to deal with that. Third, you’d have to deal with all the water it created and lastly it would be REALLY LOUD.
Yeah, it just wouldn’t work.
Now, the mobile AC units you can buy are designed to deal with all of this.
