I tried blue foam insulation first but it can't take the heat - rigid fiberglass worked fine. You may be able to overcome the heat loss with 2 steam...
If you're using the Ealex you will have plenty of steam. Go nuts insulting the box and make a steel backer with end blocks. You have to compress the...
I have an Earlex steamer. Works well but only runs for an hour before it's out of water. With two, you could stagger the start. The biggest issue is...