{"id":710,"date":"2019-01-27T18:39:39","date_gmt":"2019-01-27T18:39:39","guid":{"rendered":"http:\/\/hangar92brewery.com\/blog\/?p=710"},"modified":"2019-02-03T15:38:47","modified_gmt":"2019-02-03T15:38:47","slug":"boil-off-test-on-my-small-kettle","status":"publish","type":"post","link":"http:\/\/hangar92brewery.com\/blog\/2019\/01\/27\/boil-off-test-on-my-small-kettle\/","title":{"rendered":"Boil-off Test On My Small Kettle"},"content":{"rendered":"

\"\"<\/a>On Sunday, January 27, 2019, I conducted a boil-off test on my small kettle. It is a 62-quart SS Bayou Classic that I have used for five-gallon batches for years. I have been experimenting with lid-on boiling with my 1\/2 BBL system with the BrunDog condenser unit<\/a> and wanted to trying boiling with the lid on on the small rig to save boil-off while using less electricity with a lower PWR setting. The lid has some holes in it from prior experiments. I think there will be adequate vaporing through those holes for the wort to get rid of the unwanted stuff. Of course, I will have to actually try it to make sure.<\/p>\n

11:00 AM: I started with about 7.5 gallons of water in the kettle at 65\u00b0F. I put the lid on and applied 100% PWR.<\/p>\n

11:35 AM: A full hard rolling boil (likely started a little sooner that 11:35.) Cut PWR to 50%.<\/p>\n

11:39 AM: Hard rolling boil. Cut PWR to 30%.<\/p>\n

11:45 AM: Nice rolling boil. Set PWR to 20%.<\/p>\n

11:47 AM: Slow boil. Set PWR to 25%.<\/p>\n

11:55 AM: Adequate boil.<\/p>\n

12:10 PM: Nice boil.<\/p>\n

12:20 PM: Nice boil.<\/p>\n

12:44 PM: Perhaps a more rigorous boil than needed.<\/p>\n

12:55 PM: A bit more boil than required. Set PWR to 23%.<\/p>\n

1:05 PM: Adequate boil at flame out (FO).<\/p>\n

The volume after FO was about 7.2 gallons at approximately 210\u00b0F. The water will need to cool to get a better reading. At the current volume, the boil-off was surprisingly low at about 0.3 gallons over a 90-minute boil. When I boil with the lid off, I usually expect a two-gallon+ boil-off.<\/p>\n

I looks like a PWR setting of about 23% will do the work. I am used to using about PWR=60% with lid-off boiling.<\/p>\n

3:30 PM: T=150\u00b0F, Volume = 7.0 gallons. So, 210\u00b0F – 150\u00b0F = 60\u00b0F delta. 7.2 gallons – 7.0 gallons = 0.2 gallon delta. That’s 0.2 g \/ 60\u00b0F = 0.00333 g\/\u00b0F.<\/p>\n

Predicting the volume when cooled back to 65\u00b0F:
\n210\u00b0F – 65\u00b0F = 145\u00b0F.
\n145\u00b0F x 0.00333 g\/\u00b0F = 0.483 g<\/p>\n

So, 7.2 gallons at 210\u00b0F is predicted to be 6.7 gallons when cooled back down to 65\u00b0F.<\/p>\n

Original volume: 7.2 g
\nFinal volume: 6.7 g
\nBoil-off: 0.5 g<\/p>\n

Boil-off rate 0.5 g \/ 90 min. = 0.005365 g\/min from beginning to end.<\/p>\n

Monday, January 28, 2019, 9:30 AM: Kettle T=58\u00b0F. Kettle volume = 6.9 gallons. Boil-off loss = 7.5gal – 6.9al = 0.6 gallons.<\/p>\n

Now to brew a batch!<\/p>\n

UPDATE: 02\/02\/19: Brewed the my first batch with the lid on the kettle, a maibock at 13.7 Brix pre-boil. Sparged to 6.5 gallons and boiled for 120 minutes at around 23% PWR. I kept adjusting the power until it settled in to a nice boil. After flame out and chilling the wort to 46\u00b0F, the volume was right at five gallons. I added some distilled water to get to my target of 5.3 gallons. So, 6.5 – 5 = 1.5 gallons of boil-off over the 120 minute boil. 0.75 gallons per hour. That is substantially higher than the 0.33 gallons per hour I calculated with the water test. Now to see if the beer tastes good.<\/p>\n","protected":false},"excerpt":{"rendered":"

On Sunday, January 27, 2019, I conducted a boil-off test on my small kettle. It is a 62-quart SS Bayou Classic that I have used for five-gallon batches for years. I have been experimenting with lid-on boiling with my 1\/2 … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22,3],"tags":[113,114],"class_list":["post-710","post","type-post","status-publish","format-standard","hentry","category-education","category-equipment","tag-boil-kettle","tag-boil-off"],"_links":{"self":[{"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/posts\/710","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/comments?post=710"}],"version-history":[{"count":7,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/posts\/710\/revisions"}],"predecessor-version":[{"id":718,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/posts\/710\/revisions\/718"}],"wp:attachment":[{"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/media?parent=710"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/categories?post=710"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/hangar92brewery.com\/blog\/wp-json\/wp\/v2\/tags?post=710"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}