EM6910 Backflush - no longer 'sneezing' at pressure

[bryonvp]

Hi guys,

I have searched through the forum and have not found an answer specific to my question.

I have a 3 month old 6910, doing only 2 double shots each day. Have done monthly descales (removing the shower screen) and up until recently 2 water-only backflushes with the single walled double basket and rubbper puck, and fortnightly chemical backwashes with cleaning tablets.

Up until a couple of weeks ago, almost all backflushes resulted in the pressure guage peaking, with a 'sneeze' sound at it's peak. Recently, the pressure rises and there is no 'sneeze' noise - just a timeout and the pressure releases without the sound.

Is this normal, or is there something suspect starting to happen. The pressure guage still seems to work fine (noted it seems to stop working when the 'sneeze' thing stops for other people having this issue.)

Thanks in advance for any advice!

[Robbks]

do you get the backflush water actually drain into the drip tray..?

you should only let the gauge peak for a short time. like 1sec or less.

[bryonvp]

Hi Robbks,

I have not noticed - I'll have a look and report back. I don't allow it to hold pressure for long in fear of destroying any seals

[bryonvp]

Hi again,

I gave it another backflush this morning, and it does give a healthy full burst of water into the drip tray after stopping the 'pour'. I thought I remembered that the machine either made the noise as the pressure built up automatically (ie I didn't have to stop the pour), or the machine just stopped by itself at this point (overpressure?)

If the behaviour I am experiencing is normal, I'm happy. It's still making great coffee, but I'd end up with serious withdrawals if I had to send it in for repairs!

[Robbks]

as long as your pressure and flow through the puck is normal, and the release valve to the drip tray is obviously working properly, you're golden.

[barri]

My old 6910 had exactly the same problem bryonvp but it was intermittent. As soon as the gauge peaked I stopped it. I stopped using the automatic backflush routine after that. The machine is still working after many years so don't worry

[bryonvp]

Thanks for the replies guys. I'll keep an eye on it, but happy now that it's doing it's job (just leaking a bit around the group head seal unless I put heaps of force onto the handle which concerns me that I could be wearing out the collar prematurely - sunbeam has kindly given me a replacement seal to try so fingers crossed...)

[Robbks]

make or buy a shim to pop under the seal. and space it down a little.
I made one from an ice-cream tub lid

[bryonvp]

Thanks Robbks,

I'll give that a try. I'm guessing the portafilter should not require excessive force and sit with the handle at 6o'clock position normally.

[Robbks]

my handle was over around 5 o'clock with a new seal and shim fitted, but did not require excessive force to lock it in.
you could feel it mesh with the seal and then tighten a little more.