the good news is the pressure transducer is easy enough to install if you have the very early LR model without the relay, and even easier if you have the current LR with the relay (which the pressure transducer eliminates)
so i am comfortable that users will find it straight forward to upgrade their LR
we have some fine tuning to do; the programming needs to be altered to hold the pressure set by the user (it currently defaults to 3.0 bar every time the machine is turned off) and we need to put a delay on how often the pump cuts in restore the pre-infusion pressure to the set pressure
for example, if the pre-infusion pressure was set by the user to 3.0 bar, as the water soaks down into the puck the volume of the pre-infusion circuit in effect increases and so the pressure drops
the pressure transducer obviously detects the smallest drop in pressure and so the pump is coming on for a fraction of a second to lift the pressure by a fraction of a bar back up to the target pressure of 3.0 bar
with the pump cycling on and off many times in a second to maintain the pre-infusion pressure at 3.0 bar it results in a noise that will cause the nervous owner to ask if anything is amiss and the last thing i want is a flood of emails arising from a cosmetic issue of this nature. so we need to add a delay in, perhaps the pump will not turn on until the pre-infusion pressure has dropped 0.2 or 0.3 below the target pressure, for example. this should make it sound less erratic, and reassure owners that their machine continues to function normally
other than those two issues it worked exceptionally well 'out of the box'
i will update you again when we place the production order, and after that it is simply a waiting game for the producer to deliver them to us, probably in September or October i imagine