I'm looking for some input on keeping pigeons off of and out of an air exchanger at a mechanic shop. Will spikes on top be a good option? Do I need to build a cage around it or can netting or wire mesh be attached directly to the unit?

Maybe a PM?

If you don't get anything here, you may want to try:

www.nixalite.com

or

www.bird-x.com

Was doing some research to keep birds off our fence. Nixalite sells a product that will keep birds large and small off a surface.

Never done business with either of them, but I'm sure that they've done this kind of exclusion before.

I did end up with a bird-x product (shipping error), some plasticbird spikes, and would not recommend those.

I think the spikes will be the ticket for on top of the unit, but they also go inside it. That's what I still need to figure out. Thanks for the links.

I would think that if you watched, or got some video footage of how they enter that air exchanger, you would have a better idea of how to proceed.

I can't remember if it was nixalite, but I do know that some sites (www.wildlifecontrolsupplies.com for one) sell netting which might be used to cover the entrance. The only thing you'd obviously have to be concerned with is how strong the airflow is--don't want any of that stuff getting sucked into the unit or block airflow.

I'd send a pic to Nixalite and ask them: I'm sure this isn't the first they've seen.