Window AC fan question

[coolguy4]

Hello everyone, I am wondering why every single window AC unit that I know of is designed to suck air in through the sides and exhaust it out the back. The problem with that is the condenser gets dirty on the inside of the unit and the only way to clean it is to remove it from the wall or window, take the case off, and take the fan and shroud off or unscrew the condenser and carefully move it back a few inches so it can be scrubbed clean with a brush. As someone who has 3 window AC units, this pisses me off to no end to have to remove and totally dissemble the units every year to clean the condenser when this would be a non issue if the unit was simply designed to suck air in the back and exhaust it out the sides and top so the crap built up on the accessible part of the coil.

And to make matters worse, the buildup is often hard and really stuck to the coil because window AC units are usually designed so the pan collects condensate water for the fan to fan splash onto the coil to help cool it off. Although likely effective, the wet coil collects a lot of crap and it dries on the coil as very hard sheets that eventually block almost all the airflow.

Lots of perfectly good AC units are getting thrown out because of this stupid flaw. I have gotten several AC units from the trash that needed nothing more than a through cleaning to work perfectly. Just a few days ago my neighbor gave me a 5 year old unit because it wouldn't effectively cool her house anymore. All it took to fix it was about an hour of my time to take it apart and clean the condenser because it was almost totally plugged. This isn't even the worst one I have seen. I showed this to her and she was shocked that the inside was so filthy because she always rinsed the back of the coil every couple months to try to keep it clean. This is what it looked like window ac.jpg

If any of you see a reason why these units need to be designed in this stupid way please let me know because I see no reason for that nonsense other than planned obsolescence.

[RANGER1]

coolguy4,
I think you have answered your own question on design.
If in dusty, humid or polluted air would not help.

To filter outside air might be difficult & ugly, but could be done if plenty of surface area, never seen it though.

All design the same (could they all get it wrong).
Water or moist air over condenser coil.
cooler air over compressor.

[frank]

Haven't much experience with 'Window Rattlers' as they are not popular in the UK.

Have you thought of using a disposable media in front of the coil. https://uk.rs-online.com/web/p/hvac-...B&gclsrc=aw.ds

Might still be a pain to change but should improve having to deep clean the coil every year

[coolguy4]

coolguy4,
I think you have answered your own question on design.
If in dusty, humid or polluted air would not help.

To filter outside air might be difficult & ugly, but could be done if plenty of surface area, never seen it though.

All design the same (could they all get it wrong).
Water or moist air over condenser coil.
cooler air over compressor.

Filtering the air is in interesting idea, I thought about putting screens over the vents. If i could get 2 years out of it before having to fully dissamble the unit for a deep cleaning that would be nice. I would need to do testing to make sure that the airflow isn't restricted as that would cause the exact problem I am trying to avoid.

I think a puller fan would still splash the condenser with water if it had the ring around it, but it may be a bit less effective since the water wouldn't be getting blown through it. Never thought about the airflow over the compressor, good thought. But in either case, there is no doubt in my mind that the performance and efficiency penalty from a severely plugged coil like the one in the pic above is far greater than what would be lost from warmer air over the compressor and less effective evaporative cooling.

My thought is the manufacturers are probably just designing for maximum performance on day one with no concern for longevity or overall performance over the life of the unit. After all, building a quality unit that runs trouble free for 30 years isn't nearly as profitable as keeping customers buying new units every few years.

[RANGER1]

Filtering the air is in interesting idea, I thought about putting screens over the vents. If i could get 2 years out of it before having to fully dissamble the unit for a deep cleaning that would be nice. I would need to do testing to make sure that the airflow isn't restricted as that would cause the exact problem I am trying to avoid.

I think a puller fan would still splash the condenser with water if it had the ring around it, but it may be a bit less effective since the water wouldn't be getting blown through it. Never thought about the airflow over the compressor, good thought. But in either case, there is no doubt in my mind that the performance and efficiency penalty from a severely plugged coil like the one in the pic above is far greater than what would be lost from warmer air over the compressor and less effective evaporative cooling.

My thought is the manufacturers are probably just designing for maximum performance on day one with no concern for longevity or overall performance over the life of the unit. After all, building a quality unit that runs trouble free for 30 years isn't nearly as profitable as keeping customers buying new units every few years.

Water from evaporator would also need a slightly lower pressure to draw it outside to condenser at a guess.
Filter would still have to be cleaned regularly, so not sure on your access for that.
A pleated or flat filter could be the go along each side with filter material having a gap between it & vent, sealed on outer edges of course.
Put a ribbon on outlet to monitor air flow

[seanf]

Some daft thoughts for ya.
what about changing the condenser coil to something like a plate heat exchanger, and put a cooling loop in with its air cooled coil somewhere easy to access, link all three to the one loop.
Or flexi hoses for the inlet and outlet of the condensor, make a wee hinge so that you can swing the coil out of the unit.

[RANGER1]

Split system, still have to clean though!

[coolguy4]

Hmm I like the idea of replacing the condenser with a heat exchanger and cooling the fluid with an external radiator/fan setup that would be easier to get to. However, I'm not sure the cost and labor would be worth it. Flipping the fan blade around or removing it and installing some type of easily removable pusher fan on the back of the coil would be a more practical solution for me. Removing and cleaning the units every year isn't that much of a hassle, it just seems like a stupid design IMO since most people don't clean their units and have to replace them prematurely as a result of a bad design.

Also, to be clear, I have no problem whatsoever with cleaning coils, I rinse off my mini split's coil every month or so and thoroughly clean it twice a year before cooling season and again before heating season. It just pisses me off that window units are designed in a way that cleaning them requires removal and total disassembly as part of regular maintenance when doing so would be totally unnecessary if they were just designed to suck air in through the back and exhaust it out the sides.

[Brian_UK]

Bear in mind that window rattlers are designed such that they can be installed at any floor level.

Being on the thirty second floor makes cleaning the outside of the unit somewhat tricky, hence the ability to withdraw the unit into the room that it serves for cleaning.

[coolguy4]

Bear in mind that window rattlers are designed such that they can be installed at any floor level.

Being on the thirty second floor makes cleaning the outside of the unit somewhat tricky, hence the ability to withdraw the unit into the room that it serves for cleaning.

That's a great point, I never thought of that. However, even if the unit still had to be removed for cleaning, it would be a lot easier to clean the crap off the back of the unit than to have to completely disassemble it for cleaning, which people almost never do. Lots of people don't realize that they have to since the crap builds up in an invisible place and many of the people that do realize are afraid to disassemble the unit because it often isn't a very straightforward process, especially for less handy people.