Advice ? My Air conditioner stopped midday during camping...

[09 harley]

Originally Posted by backtrack15

I’m curious if you tried using tape to change the bars from U to D and measured the air flow? Regardless, thanks for the interesting tip regarding the U shape.

I didn’t do that because in effect you would have a flat surface you were forcing air over. Kind of like a bunch of class A’s going down the freeway with perfectly flat fronts. The airflow would be pretty poor.

[09 harley]

Originally Posted by Fotoguzzi

Pictures of the u shape things would be more than nice to understand where to cut etc.. pics anyone?

Found some!
Existing bars. Inside view after cutting out and taping in screen. Outside view.

[09 harley]

Originally Posted by Fotoguzzi

Pictures of the u shape things would be more than nice to understand where to cut etc.. pics anyone?

Found some. Before. Fins cut out. Screen attached. Outside view.

[09 harley]

Had a little trouble posting pictures

[Bo Walker]

Well Harley, I was going to cut mine and install screen. But I found mine is completely different. The cap is solid with no openings. On the bottom underneath the cap in the metal that the cap is fastened to has large holes for air. The holes are on both sides and the end. I don't know if this is the most efficient or not. I see no way to improve it.
I installed my run capacitor replacement yesterday and the unit is up and running now.

[Fotoguzzi]

Originally Posted by 09 harley

Had a little trouble posting pictures

Thankyou for posting the pics. Did you just do the rear? It looks like the sides are left original?

[R2D2]

09 harley.,

I don't see any reason that modification wouldn't be more efficient at moving air. Thanks for sharing that tip! Curious though why you think screen with larger openings would not work as well as the smaller screen openings? Larger openings would seem to be logical, especially based on your example. Maybe the system needs at least some resistance to function?

[backtrack15]

Now that I’ve seen the photos, I agree the outlet design was pretty restrictive. I don’t think the “bar density” is quite as high on my AC. I’ll definitely take a look next time I’m on the roof.

[09 harley]

Originally Posted by R2D2

09 harley.,

I don't see any reason that modification wouldn't be more efficient at moving air. Thanks for sharing that tip! Curious though why you think screen with larger openings would not work as well as the smaller screen openings? Larger openings would seem to be logical, especially based on your example. Maybe the system needs at least some resistance to function?

My understanding is that the larger cross sectional density of the larger wore size caused increased turbulence. A round surface creates more as the size increases. If the round surface had a kamm rear design that would help, but it doesn’t. A smaller size works better in most cases. When you are at the hardware store next time. Try blowing on different screens and you will be surprised by the blow back you feel. Don’t do this for too long a time because someone usually calls the men in white to come take you away.
Also the side vents on my unit are the intake. I could probably increase this flow by filling the bars in. I made a decision to just accept this.
For anyone who hasn’t used an anemometer try to find one to play with. Lots of HVAC guys have them for measuring air flow when adjusting the flow from registers.

[R2D2]

Originally Posted by 09 harley

My understanding is that the larger cross sectional density of the larger wore size caused increased turbulence. A round surface creates more as the size increases. If the round surface had a kamm rear design that would help, but it doesn’t. A smaller size works better in most cases. When you are at the hardware store next time. Try blowing on different screens and you will be surprised by the blow back you feel. Don’t do this for too long a time because someone usually calls the men in white to come take you away.
Also the side vents on my unit are the intake. I could probably increase this flow by filling the bars in. I made a decision to just accept this.
For anyone who hasn’t used an anemometer try to find one to play with. Lots of HVAC guys have them for measuring air flow when adjusting the flow from registers.

I have some experience with aerodynamics, so I get that.

After giving this more thought, is the screen even necessary? I assume there is no screen there to begin with (no ladder, so I can't verify). What if you just removed the bars? Obviously the screen is for bugs, but if they can get in anyway, does it matter?

[Fotoguzzi]

Originally Posted by R2D2

I have some experience with aerodynamics, so I get that.

After giving this more thought, is the screen even necessary? I assume there is no screen there to begin with (no ladder, so I can't verify). What if you just removed the bars? Obviously the screen is for bugs, but if they can get in anyway, does it matter?

Yeah, do I really need a screen?