Aside from adding an elbow, one method to allow finer mesh without blocking airflow is to extend the mesh a fair distance - I'll try to get a picture of Something similar, but doubt I can find the exact thing I'll want - basically either a long (12"/30cm or so) mesh tube, or a 12-18" section of pipe, drilled full of holes, and then wrapped in mesh small enough to keep the wasps out. When you make the mesh smaller, you need more area so that the flow can remain the same (even if some parts are blocked) - so the idea is to greatly increase the area of mesh.

OK, these are fish pond filters, but they have the right idea.



Some car or truck air filters might actually be adaptable to work, too - especially the "aftermarket high flow" types (you might ditch the "foam filter" those have and just use the "mesh cage" part of them) - but that's more if you want something you can buy - you should be able to make something that works out of ordinary hardware cloth mesh.

How can I prevent the intake vent for an on demand water heater from getting plugged?

  &nbsp;&nbsp;"You know how I think they choose people for the Gryffindor team?", said Malfoy a few minutes later, as Snape awarded Hufflepuff another penalty for no reason at all." It's people they feel sorry for. See, there's Potter, who's got no parents, then there's the Weasleys, who've got no money – you should be on the team, Longbottom, you've got no brains."
  &nbsp;&nbsp;Neville went bright red but turned in his seat to face Malfoy.
  &nbsp;&nbsp;"I'm worth twelve of you, Malfoy," he stammered.
  &nbsp;&nbsp;Malfoy, Crabbe and Goyle howled with laughter, but Ron, still not daring to take his eyes from the game, said, "You tell him, Neville."
  &nbsp;&nbsp;"Longbottom, if brains were gold you'd be poorer than Weasley, and that's saying something."


What does Ron mean by the phrase "You tell him, Neville"?
