Launderess:
Condenser dryers (as opposed to Heat Pump dryers) get less efficient above 110F ambient temperature, and 69F is very much in the ideal range. The air circuit inside the dryer is a closed circuit and ambient humidity / dew point shouldn't affect the dryer much -- what you just described, 69F, dew point of 69F and ambient humidity of 89% means a couple of things, (a) it's probably raining or about to rain in your location and (b) those are *much* more likely to adversely affect a *vented* dryer, because a vented dryer is *most* efficient when ambient air is warm and dry, given that the dryer will get ambient air, heat it and circulate inside the load before exhausting it.
A condenser dryer takes air from inside the tumble drum, cools it down (thus condensing the water), warms it up again and sends it into the drum -- the air circuit isn't sealed, but there's very little exchange with the ambient air. The circuit that cools the condenser takes air from the room, circulates it to cool the condenser and is expelled back into the room. In a properly functioning heat exchanger (the condenser part) there's only *heat* exchange, not moisture.
The temperature differential (the air inside the dryer is at 140F or so, while the ambient air is around 70F or so) is more than enough to saturate the air circulating inside the drum with water that then condenses out.
We're also talking about dryers which have at most 1,500W heaters (your portable) and dryers that have around 3,000W heaters. While I have *no* trouble believing you that your Lavatherm is not behaving optimally because something is broken (air leak in the condenser and/or drying circuit, making the condensing inefficient and/or leaking moisture into your home), you will have to excuse me for not believing you when you tell me that your 1.5kW dryer (120V, 15A) is faster than your 3.0kW (240V, 15A) dryer, whether or not AEG told you whatever they told you, I'm more likely to believe AEG wanted you to hang up the phone, given that they don't care about our market, they never even offered their machines here, they were imported from Canada.
All I can tell you is that my experience with a similar Bosch is that I get 5kg of clothes dry in 60-80 minutes, depending on stuff like it's a load of bed sheets, t-shirts, jeans or towels. I've used this dryer in all kinds of weather, rain or dry, 50-90F, and the machine worked just fine. It needs to be above 100F for me to even notice that it takes another 5-10 minutes extra to dry.
My experience with Miele condensing dryers was fairly similar.
The experience of people who show up here and/or ThatHomeSite/GardenWeb/Houzz seem to match mine and even people who extensively discussed their experience importing the AEG set from Canada into US (at that time it was ThatHomeSite) seemed to be overwhelmingly good and some of them lived in Los Angeles, some in San Francisco, but I remember there were people in NYC too and in all these years, I seem to remember only *you* complaining about your AEG and another person, whose name I've spaced out right now, but had a similar complaint about her Asko dryer that, surprise, surprise, turned out had a problem in that the condenser wasn't sealing properly, so hot, humid air was escaping into the room instead of condensing.
The most vocal folks complaining about condensing dryers are folks in US, who are used to a 6.0kW (240V, 30A) machine and well, of course you can't match that speed with only half the resources. Some of those people, I'm sure, would also complain about how a regular domestic dryer is crappy because the 50 pounder dryer at their local laundromat can finish their 15-pound load in less than 20 minutes and the domestic dryer is taking 60 minutes or so.
But here's the thing -- an Euro dryer which uses 240V/15A and is a vented dryer is only a bit faster than the equivalent condenser dryer, usually by 5 to 15 minutes only. I know this because I *have* used side-by-side dryers that were identical except for one was a Miele condenser dryer and the other was a Miele vented dryer. I am willing to bet most of the difference is because the condenser dryer takes a little bit longer to cool down the load because of the way it has to get rid of the heat.
I've also used a "portable" vented dryer extensively, and times for a 5kg load were in excess of 120 minutes. Efficiency fell sharply with cooler rainy (humid) weather.
So, something is very wrong with your account of events.
Given how trustworthy you have proved yourself over all these years I've read you online, I am sorry, but you leave me no option but to believe your AEG Lavatherm is defective somehow.
And I do hope you get if fixed someday.
Peace,
-- Paulo.