Cleansing an incubator

Hi Folks

I've recently started with incubators and have a shiny new Brinsea Advance, but I've also managed to get hold of a very old Brinsea Octagon 10. It appears to all be working and I know they are tricky to use, but I have some eggs that I'd like to set but the incubator looks quite dirty. I don't have any incubator cleaner and no-where to get it locally - would very diluted Poultry Shield work, if it's well rinsed afterwards?

I'm wondering if it will be too strong even after dilution or possibly leave a residue that will penetrate the eggs.