[skyler]

Finally used my 17.4 gallon Penrose kettle. I put a weldless thermometer on it at about the 4 gallon mark. The kettle worked great, despite not having a lid, but my evaporation rate was insane. 8.5 gallons boiled down to 4.5 in just 90 minutes. The boil was slightly more vigorous than usual, but nothing extreme. All I can think is that the wider diameter combined with no lid means more evaporation. My wort also went into the fermenter much clearer than usual. I am wondering if this is also due to the kettle geometry. Also, should I expect 2.66 gallons per hour to boil off even if I brew a 10 gallon batch?

[brew_in_stl]

Nice to hear you got it okay!  UPS didn't beat it up too bad, did they?

As far as the evaporation rate, while "stlaleman" can probably give you a little better insight into this, I have noticed about a 1.5 gallon/hour evap. rate with my beers, regardless of batch size.  I have done many a five gallon batches, a couple ten gallon batches, and one 13 gallon batch (was nervous as all get out at initial boil!).  Noticed about the same loss every time.

Hope this helps a little until the "mastermind" jumps in!

[stlaleman]

Not sure I like the term "mastermind".......Anyway, congrats on the vigerous boil! I tend to loose about 1.5-1/75 gallons per hour myself and folks tell me I boil hard! The plus side is, as your batches get larger, you'll boil off the same amount, as loss is do to surface area not depth. You have two choices, collect your wort as usual and add water to equal your loss or turn down your heat. I, myself, like the hard boil, better hop utilization and more undesirable flavors/aromas driven off.
Am glad you like it, a little fine tuning and everything should be good to go.

[skyler]

I moved my propane today and it felt awfully light for just 3 5-gallon batches on it, so I must have had a much more vigorous boil on this one than I thought. WIth all that extra space (and the anti-foam), I must have just thought it was boiling less vigorously. I'll be trying it with my first 10 gallon batch this weekend. The plan is to start with 14 gallons (hops will absorb 1 gallon, minimum).

[skyler]

I thought it worth mentioning that I have figured out how to tackle the "no lid" issue. 2 cookie sheets (the kind that have no ridges) will completely cover the top, or I can have it to that there is just enough space for an IC to stick out. I use the cookie sheets when I want to get the boil started, am heating strike water, or I am cooling my wort outdoors (though my usual method is to carry the beast of a kettle into my bathroom and hook the IC up to the showerhead pipe).

My only gripe is that it is very difficult to screw my bazooka screen into the coupler welded onto the front of the kettle. If I could do it again, I think I would prefer it to just have a hole for the coupler, so I could use a weldless coupler.