Bird Deterrent?

[Adventure.AS]

I have some Red-Winged Blackbirds trying to build a nest inside the shroud of the roof top air conditioner. I have pulled out the twigs and grass etc., but hope someone might know of an effect deterrent.

[GMFL]

A. B.B. gun. “an official Red Ryder, carbine action, two-hundred shot range model air rifle!”

Be careful not to shoot your eye out.

You said it best.
“One test is worth a thousand 'expert' opinions”

[nomadleslie]

Put a rubber snake or a fake owl up there. Should do the trick. You don’t want to ding your Airstream with a stray shot. Best to “first, do no harm,” though I’ve known plenty of people who have had success with both B.B. and pellet guns.

[Gamehawkers]

Consider installing screening material.
Hardware cloth with 1/4 inch squares should not interfere with airflow but prevent them from getting sticks inside the cover. I would test it by making a box of the wire that covers the whole ac unit. If that is effective, I would then entertain removing the plastic cover and cutting pieces of hardware cloth to fit inside the cover’s vent holes and tape in place with Gorilla tape. Replace the plastic cover and see if that solves the problem. If it works perfectly you can consider using epoxy to make it a forever fix.
By doing it in stages you can evaluate and stop at any point if it fails the test before making the fix last forever.
Best of luck to you

[rmkrum]

Agree with Gamehawkers cure for bird invasions. It's been used before.

Another possible issue is mud dauber wasps and other insects getting inside the shroud. 1/4 inch hardware cloth will not keep them out very well.

Some on the forum have used aluminum window screen epoxied into the air openings. The downside is that it gets dusty and dirty and eventually restricts air flow. Then it becomes a pain in the butt to clean it regularly.

If you are not having issues other than birds, the 1/4 inch mesh hardware cloth is the best solution. It's always a good idea to pull the shroud as part of preventative maintenance each season to inspect the interior of the AC unit, check for bug nests, and lubricate and clean motors and fins as needed...