Anyone seen this Grainfather issue?

[strange-steve]

I've noticed this happen a few times before, as you can see there's a lot of foaming occurring during the mash. That foam isn't coming from below, the bubbles are coming through the recirc arm.

Any idea what's happening here? Air being pulled into the pump system somewhere? Off-gassing from one of the grains? It only seems to happen during the mash, and usually only after the mid-mash stir.

 

[hop-a-long]

I've noticed this happen a few times before, as you can see there's a lot of foaming occurring during the mash. That foam isn't coming from below, the bubbles are coming through the recirc arm.

Any idea what's happening here? Air being pulled into the pump system somewhere? Off-gassing from one of the grains? It only seems to happen during the mash, and usually only after the mid-mash stir.

Hi SS,
Looks like you've got quite a bit liquid on top of your mash.
The foam could be the result of to little liquid under your grainbasket.
The obvious solution would be to limit the flow through your pump by partially closing off the valve on top of the riser.

I've noticed someting similar happen with a closed grainbed.

 

[strange-steve]

You could well be on to something there. I did have the pump turned down a bit but probably not enough, there was a load of oats and wheat in there so it was a very sticky mash. Next time I see it I'll try turning the pump down more

 

[Deadhead]

Yeah, I seem to have this issue when the liquid doesn't seem to make it through the mash enough to keep recirculating. If I am making something with lots of oat and wheat, I need to use rice hulls.

 

[Saisonator]

Only time I had that was from a poor seal where the flow control is on the recirculation pipe.
I just replaced an o-ring and have had no issues since.

 

[cjibbo]

Just read this thread and after checking the recirc arm on mine I notice the oring that sits between the valve assembly and arm had disappeared. Corny post oring fitted and fixed the issue.