Question about Spike Kettles

Can anyone report on the performance of the sight glass on Spike kettles? Specifically, does the wort inside the sight glass move around a lot during the boil?

http://spikebrewing.com/collections/10- ... ss-kettles

I know this won’t answer your question specifically about the Spike kettles but I noticed with my Blichmann, the wort would start boiling if I didn’t have it positioned properly over the heat shield. If you don’t have a heat shield of some sort to protect it from the burner you may experience something similar with the Spike kettle.

Thanks Matt.

I had noticed that the Spike kettle has a shield under the sight glass, however it’s not advertised as a heat shield. Wondering if it serves that purpose or if a separate heat shield would be required. The sight glass is also offset a bit, rather than (like the Blichmann) hugging the kettle–which could potentially make a difference?