San Franciscan Roaster gas Jets Cleaned, and thank you for returning your jars.

Last week, for the first time ever, we cleaned the orifices on each of the brass jets for our SF-25. We had been debating our gas flow for months, but finally a week ago our afterburner started to cut out (totally separate issue from the jets). This led us to schedule a day without roasting, midweek- especially important, since supply houses and emergency mailings cut out over the weekend. There were many tiny screws to remove, but starting on the afterburner we are never really sure, but somehow cleaning the spark-plugs, or ignition points, and checking air to the gas- well it worked.

Luckily the afterburner (incinerator) stopped working on some misty and rainy days. Coffee smoke is organic matter, but drops out in mist, or rather gets caught in the water molecules. Coffee smoke is a lot of oils, and carbon, and other gases. Normally we only run our roaster just over 1100 Fahrenheit (593.33 Celsius). which is the magic number where visible particulate matter breaks down, or SMOG. it still smells until 1400 F. (760 C.) It smells but the smoke is clear. Since there has been a roastery here working for at least 25 years, it seems to be ok in the neighborhood (the neighbors mostly do not know we are here).

With the afterburner magically fixed, although we have no idea why, in under 30 minutes, well we thought we would look into our longterm problem. the gas jets.

The reason why we had never undertaken cleaning of all of the tips, is that, in order to remove them you either have to spend a lot of time, very awkwardly, and painfully removing them in place, or, drop the burner itself. Dropping the burner, or the welded square tubing running parallel under the drum requires the removal of the gas line in three points, and gas lines are not exactly our specialty. Since we had the day, why not.

Remarkably, we dropped the burner down so we could access, and after checking the build up on the nipples were about to put it back and give up, but…. and this took us a minute, to discover the tiny pinholes where the gas went through were more than clogged with precipitant, or calcium carbonate i assume. Now. for a long time the front few jets had been very difficult to light. This involved a trick by cutting airflow to ignite all the nipples. But the last year always a few never lit, which we always thought was a draft issue. So, very carefully using a safety pin we cleaned each orifice on each jet. We noticed while re-installing that the threading on the burner was off, and some of the jets had almost been crossthreaded. With the gas lines reinstalled, the results were amazing.

So the last winter we had been doing 3 batches an hour at 12 pounds, and having a hard time with it. Today, after the maintenance we are doing almost 5 batches an hour, and dropping in 18 pounds. This seems more inline with our friends roasting on 1950′s Probats (the ratio of beans on a similar sized drum). When we first started roasting we were dropping 15 pounds and four batches an hour. Cleaning jet orifices has made such a huge huge improvement.

Other news, someone returned about 28 jars the other day- thank you. Please dont recycle your widemouth mason jars but re-use. Selling in glass is hard for us, but glass is preferable to paper, and so so so much better than plastic- as we are the only roaster in portland not packaging in plastic bags, we are excited to offer glass, and to re-use. thank you.

More other news- Japanese shaved ice saturday went smooth. Strawberry Rhubarb was the favorite. more of that next saturday.

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