shadowfax wrote:I would suggest you try paying attention to the heating element activity as you brew. I noticed on valentina that the pump worked a LOT better when the heating element was OFF... I think it has to do with the power draw of them both, together, being a little more than the circuit can deliever for... If I understand right, this is one reason that a 220V machine is better--you can supply the element and pump concurrently much better.

However, to ensure "mutual exclusion" of the pump and the heating element, try this. When you flush, you'll notice the element comes on from the pressure drop that accompanies the introduction of the cold flush water. Usually, it will still be on when the flush is finished. Try locking in your prepared shot right then and start it before the element goes off. This way, more "cold" water comes in before the element goes off, and it takes it a little longer to get all the way back up. And In my experience, the heating element goes off about 5 seconds into the shot, meaning it goes off before the pressure ramps up and the pump bogs down. The effect of this means the element doesn't come BACK on until late in the shot, about 25-30 seconds in, when you're about to kill it... and that usually means that the pump will have higher pressure on it. Just an idea to try. I don't know how temperature stable this idea is, I never had the tools to check it...