(Before jumping in: THANK YOU to everyone who shares knowledge in this forum! Loving the bullet and this community!)
Just roasted for the first time after 3.5 months off. Roasted 3 batches of 1lb each. A nice Kenyan from Sweet Maria’s.
The roaster is leaking brown fluid near the rear! Pretty disconcerting. The roaster has been used a couple dozen times since it was first fired up earlier this year.
Picture? Can you confirm it is water-based (not oil or grease?). How much fluid are we talking about? Does it smell of anything? Have you taken off the chaff collector and inspected the rear of your machine?
Do you by chance have an exhaust vent hose attached to the roaster in such a way that condensation in the hose could drain back into the roaster? I recall seeing such a picture somewhere once…
Thank you David and Brad for the swift replies! Here’s a picture of the small amount of fluid that collected.
David, it seemed water based. Not much fluid at all. Didn’t smell of anything besides coffee/roast.
Brad, you might be on to something here. No exhaust vent hose. BUT I was roasting in an enclosed space but it was effectively outside, and there was high humidity. Only 70 degrees Fahrenheit but around 90% humidity.
Some bit of moisture could have accumulated during the course of the 3.5 months the roaster was idle. The vapour during preheat could be condensing in the exhaust chute and dripping down with the sediments stuck there.
I roast in Darjeeling where we have a very, very damp Monsoon. I see moisture evaporating from the front glass during preheat even with a few days break in roasting.
In my experience this is pretty normal - green coffee is around 12-15% water, and a lot of it gets turned into steam as we roast, and where that steam condenses can cause the behavior you’re seeing. I find that the environment (temperature & humidity) makes a big difference, and some beans just have more moisture to lose, so cause this to happen more than others.
I was thinking about this a few nights ago and remembered that the Loring I used to roast on would accumulate a yellow/brown tinted water in the drum as the machine was heating up after start up. This was due to the cool, very humid environment of that particular roastery.
Thanks for this thread. This happened to me for the first time the other day. My chaff filter was clogged. It was also cool and humid, I was roasting outside. 75% humidity, 15.2°C / 60°F.
Most of the brownwater leaked out the bottom but some got to the squirrel cage fan and all the surfaces around there were sticky. Not very difficult to clean.
This is pretty common. It’s nothing to worry about. It is generally down to environmental variables. The brown liquid is condensed water vapour mixed with coffee oils. Just check how clean everything is and if it’s all good, just carry on roasting. You can sometimes find it leaking from the back (chaff collector), the front (chaff vent under the door).