BrewPi for mashing tips

General
1

Finally putting all my equipment together to use BrewPi for mashing.

Can anyone currently doing this give me some pointers on their settings?

My setup is single vessel, BIAB, 60L pot with 5.5kW element. I will be recirculating using one of the newer pumps from the BrewPi store. I have one temperature probe mounted on the side of the pot at the base close to the element (and where the pump extracts liquid) and another in a T-junction at the top where liquid is being fed back in. I plan on use the bottom probe for control.

How are people controlling the boil? Ideally I would have thought it would be best to be able to disable PID control and just manually control PWM duty cycle in order to set the boil ferocity.

I’ll post some pictures of my setup when I finally have it all together.

Anyone else using BrewPi with a BIAB/single vessel setup?

2

I’m keen to see how you get on with this as I am planning a similar (although smaller) setup.

I have a 36l BIAB pot with a 2.4kw element. I’m really keen to implement PWM as currently if I do a half size batch the boil is crazy!

3

With a BIAB setup, you can just use fridge mode, with the bottom probe as fridge sensor.

I think Kp at 50 or 100 will work well, Ti at 900 and Td at 30.

For boil control, you should set Ti to zero and set the setpoint to something slightly above 100C. For example:
Kp = 50, Setpoint = 101, temp = 100 --> actuator is 50% on.

You can control the intensity with the setpoint.

4

Thanks @Elco I’ll give those settings a try. How about the filtering?

Other electric BIAB controllers I have seen have an algorithm to detect when boil is reached then switch to a preset power level (duty cycle) which can be adjusted on the fly. I’m sure your suggested method with PD control will work too.

5

Yes, that’s how we will do it in the future. This is just something that works for now.