To more directly answer the question, yes most window units are designed to collect condensate water and use it to help cool the condensor. The rear fan typically has what's called a "slinger ring" around its circumference, which serves to pick up the water and throw it against the condensor (rear) coil. There's typically a hose or two or a drain channel molded into the bottom of the unit, leading from a collection pan beneath the evaporator (inside) coil to a pan beneath the condensor coil. In cases of very high humidity, the condensor pan can overflow, resulting in water in the bottom of the unit, which will likely find its way out through any slots or holes in the bottom, around screws, from side vents, etc. If one is handy and up to the task, a small hole can be drilled into the bottom (CAREFULLY, in a strategic location AWAY from the compressor and condensor coil -- one does NOT want to put a hole in them!*), and a catch-pan attached beneath the unit with a hose to divert the flow away to a specific area, away from sidewalks, flower beds, etc. My grandfather did this with a unit that extended over their back porch, so the water would drain out to the yard instead of across the porch. (*One of my uncles attempted to drill a drain hole in a window unit many years ago, and put a hole in the compressor. I don't recall now if they had the compressor replaced, or trashed the entire unit for a new one.)

Float switches are available to mount in the condensate drain pan in the air handler to shut the system down. The switch clamps to the edge of the pan and the small square float hangs over into the pan. If the float rises it shuts down the whole system. An example is below. There are many others. I do not like the ones with the float on an arm. Here is a link that might be useful: Grainger Condensation Pan Switch

I thought we agreed that we were not going to limit the discussion to the climate of Katy Texas? Well the OP who started this thread made it sound like he lived near me... which would mean using my climate numbers as opposed to somewhere else. I don't service areas outside my climate so why on earth would I entertain this idea of yours? (I offer advice on occasion but that is all it is --- professional advice --- as this is what I do for a living, I don't sit all day in forum board --- I do have a life outside of HVAC, what little it is right now it's still a life...) You again trying to fit HVAC in a confined specific box in which it does not fit. What are the odds that someone will find that information useful? Probably close to 0% if I had to guess. That sounds like a waste of time... I know this seems productive to you so knock yourself out if you want to do that. Exact numbers are not necessary to educate everyone the source of the condensate. Then why not use the 'about 0.8 gallons estimate' and run with it? An air conditioner in my climate can produce upwards of 5 gallons of water an hour. A condensing furnace will not produce that much. An 80% non condensing furnace will produce 0 condensate water. Oh so let's use the AC condensate line for the furnace condensate. Problem solved right? Most likely not. Drain systems are complex especially when you throw in the variable that a condensing furnace imposes. See I've led your hand to this point --- where the concern right now up to this point is how much more condensate a condensing furnace will produce in my climate Katy, Texas versus other less humid climates in which those furnaces are installed typically in a basement. You don't have the over head flood threat you do here in my climate. All of this --- except: there are safeties on that condensing furnace that if you don't do it properly, the furnace will shut off on nuisance trips. So the furnace is not likely to be the cave in threat due to condensation production. They tend to leak water in drips around the furnace while having very erratic operation most often. You don't get these kinds of problems with a 80% non condensing furnace. What a home owner knows versus that of a pro... you think condensate is the only problem you have to contend with. What is your definition of making this actually work? How does the condensing furnace then become the ceiling cave in threat? Changes to the condensate drain system by people who don't know what they are doing. It may be a home owner, land lord or even a technician who doesn't understand the implications of what they are doing. How much water one produces whether here in this climate in Katy, Texas or a less humid climate (in winter) like Chicago / Wisconsin --- the different in condensate production doesn't matter... *IF* the system to get rid of condensate is adequate. This thread was about a young guy presumably in his 20's attempting to install a condensing furnace in a probable high humid climate. That condensing furnace was bought used. Who in their right mind sells a condensing furnace (used) in a probable high humid climate? One that tried to install said furnace and couldn't get it to work. I have an innate ability to read between the lines. I've seen quite a bit of 'Tom Foolery' in my nearly 26 years of doing this for a living. We can't get it to work so we'll take it out and sell it to someone else. So what makes the condensate drain system of a condensing furnace adequate? The right way. What is the right way? The opposite of wrong. If you want to learn how to do it: There are trade schools for that. Class dismissed......

Majority of washers nowdays have electric drain pumps, not driven by the main motor either via belt or directly, and drain slower than older machines. Frontloaders, of course, also involve a lesser volume of water. I recall when WP direct-drive washers were new on the market and we (the appliance service where I worked) delivered them to customers who had an older belt-drive machine ... the direct-drives discharge at a higher flow rate and the drain standpipe would sometimes overflow during the installation test-run. A workaround during the test was to set it to spin on low speed for a slower discharge rate. We'd advise the customer their drain must be serviced or reworked.